31521444516 has 30 divisors (see below), whose sum is σ = 82403283270. Its totient is φ = 10507148064.

The previous prime is 31521444511. The next prime is 31521444517. The reversal of 31521444516 is 61544412513.

It can be written as a sum of positive squares in only one way, i.e., 29241000000 + 2280444516 = 171000^2 + 47754^2 .

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

It is not an unprimeable number, because it can be changed into a prime (31521444511) 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 9 ways as a sum of consecutive naturals, for example, 48643881 + ... + 48644528.

It is an arithmetic number, because the mean of its divisors is an integer number (2746776109).

Almost surely, 2^31521444516 is an apocalyptic number.

31521444516 is a gapful number since it is divisible by the number (36) formed by its first and last digit.

It is an amenable number.

31521444516 is an abundant number, since it is smaller than the sum of its proper divisors (50881838754).

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

31521444516 is a wasteful number, since it uses less digits than its factorization.

31521444516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97288425 (or 97288414 counting only the distinct ones).

The product of its digits is 57600, while the sum is 36.

The spelling of 31521444516 in words is "thirty-one billion, five hundred twenty-one million, four hundred forty-four thousand, five hundred sixteen".