8181815620 has 48 divisors (see below), whose sum is σ = 18759117888. Its totient is φ = 2972773760.

The previous prime is 8181815597. The next prime is 8181815627. The reversal of 8181815620 is 265181818.

It is not an unprimeable number, because it can be changed into a prime (8181815627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 266379 + ... + 295501.

It is an arithmetic number, because the mean of its divisors is an integer number (390814956).

Almost surely, 2^8181815620 is an apocalyptic number.

It is an amenable number.

8181815620 is an abundant number, since it is smaller than the sum of its proper divisors (10577302268).

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

8181815620 is a wasteful number, since it uses less digits than its factorization.

8181815620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30420 (or 30418 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 40.

The square root of 8181815620 is about 90453.3892123452. The cubic root of 8181815620 is about 2015.0379483317.

The spelling of 8181815620 in words is "eight billion, one hundred eighty-one million, eight hundred fifteen thousand, six hundred twenty".