31938146257 has 4 divisors (see below), whose sum is σ = 32717125476. Its totient is φ = 31159167040.

The previous prime is 31938146213. The next prime is 31938146263. The reversal of 31938146257 is 75264183913.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 75264183913 = 9241 ⋅8144593.

It can be written as a sum of positive squares in 2 ways, for example, as 7240137921 + 24698008336 = 85089^2 + 157156^2 .

It is a cyclic number.

It is not a de Polignac number, because 31938146257 - 2²⁷ = 31803928529 is a prime.

It is a super-2 number, since 2×31938146257² (a number of 22 digits) contains 22 as substring.

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 31938146257.

It is not an unprimeable number, because it can be changed into a prime (31938146297) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 389489548 + ... + 389489629.

It is an arithmetic number, because the mean of its divisors is an integer number (8179281369).

Almost surely, 2^31938146257 is an apocalyptic number.

It is an amenable number.

31938146257 is a deficient number, since it is larger than the sum of its proper divisors (778979219).

31938146257 is an equidigital number, since it uses as much as digits as its factorization.

31938146257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 778979218.

The product of its digits is 1088640, while the sum is 49.

The spelling of 31938146257 in words is "thirty-one billion, nine hundred thirty-eight million, one hundred forty-six thousand, two hundred fifty-seven".