31815864013 has 8 divisors (see below), whose sum is σ = 32421627000. Its totient is φ = 31210303488.

The previous prime is 31815863999. The next prime is 31815864053. The reversal of 31815864013 is 31046851813.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 3971268324 + 27844595689 = 63018^2 + 166867^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 31815864013 - 2²¹ = 31813766861 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31815864053) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 288013 + ... + 382861.

It is an arithmetic number, because the mean of its divisors is an integer number (4052703375).

Almost surely, 2^31815864013 is an apocalyptic number.

It is an amenable number.

31815864013 is a deficient number, since it is larger than the sum of its proper divisors (605762987).

31815864013 is an equidigital number, since it uses as much as digits as its factorization.

31815864013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101231.

The product of its (nonzero) digits is 69120, while the sum is 40.

The spelling of 31815864013 in words is "thirty-one billion, eight hundred fifteen million, eight hundred sixty-four thousand, thirteen".