31729426513 has 4 divisors (see below), whose sum is σ = 32249581108. Its totient is φ = 31209271920.

The previous prime is 31729426471. The next prime is 31729426541. The reversal of 31729426513 is 31562492713.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 11805257104 + 19924169409 = 108652^2 + 141153^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31729426513 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 31729426513.

It is not an unprimeable number, because it can be changed into a prime (31729426013) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 260077206 + ... + 260077327.

It is an arithmetic number, because the mean of its divisors is an integer number (8062395277).

Almost surely, 2^31729426513 is an apocalyptic number.

It is an amenable number.

31729426513 is a deficient number, since it is larger than the sum of its proper divisors (520154595).

31729426513 is an equidigital number, since it uses as much as digits as its factorization.

31729426513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 520154594.

The product of its digits is 272160, while the sum is 43.

The spelling of 31729426513 in words is "thirty-one billion, seven hundred twenty-nine million, four hundred twenty-six thousand, five hundred thirteen".