217983312 has 50 divisors (see below), whose sum is σ = 630910698. Its totient is φ = 72660672.

The previous prime is 217983253. The next prime is 217983313. The reversal of 217983312 is 213389712.

217983312 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 208398096 + 9585216 = 14436^2 + 3096^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217983313) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 82803 + ... + 85394.

Almost surely, 2^217983312 is an apocalyptic number.

It is an amenable number.

217983312 is an abundant number, since it is smaller than the sum of its proper divisors (412927386).

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

217983312 is a wasteful number, since it uses less digits than its factorization.

217983312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168217 (or 168202 counting only the distinct ones).

The product of its digits is 18144, while the sum is 36.

The square root of 217983312 is about 14764.2579224287. The cubic root of 217983312 is about 601.8308078887.

It can be divided in two parts, 2179 and 83312, that added together give a triangular number (85491 = T₄₁₃).

The spelling of 217983312 in words is "two hundred seventeen million, nine hundred eighty-three thousand, three hundred twelve".