215987231700864 has 768 divisors, whose sum is σ = 728055937889280. Its totient is φ = 63285476401152.

The previous prime is 215987231700859. The next prime is 215987231700869. The reversal of 215987231700864 is 468007132789512.

215987231700864 is a `hidden beast` number, since 2 + 1 + 598 + 7 + 2 + 31 + 7 + 0 + 0 + 8 + 6 + 4 = 666.

It is an interprime number because it is at equal distance from previous prime (215987231700859) and next prime (215987231700869).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215987231700869) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 703014547 + ... + 703321709.

It is an arithmetic number, because the mean of its divisors is an integer number (947989502460).

It is a 1-persistent number, because it is pandigital, but 2⋅215987231700864 = 431974463401728 is not.

Almost surely, 2^{215987231700864} is an apocalyptic number.

215987231700864 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 215987231700864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (364027968944640).

215987231700864 is an abundant number, since it is smaller than the sum of its proper divisors (512068706188416).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

215987231700864 is a wasteful number, since it uses less digits than its factorization.

215987231700864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 307289 (or 307265 counting only the distinct ones).

The product of its (nonzero) digits is 40642560, while the sum is 63.

The spelling of 215987231700864 in words is "two hundred fifteen trillion, nine hundred eighty-seven billion, two hundred thirty-one million, seven hundred thousand, eight hundred sixty-four".