31990855133 has 4 divisors (see below), whose sum is σ = 31991287680. Its totient is φ = 31990422588.

The previous prime is 31990855129. The next prime is 31990855157. The reversal of 31990855133 is 33155809913.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 33155809913 = 19 ⋅1745042627.

It is a cyclic number.

It is not a de Polignac number, because 31990855133 - 2² = 31990855129 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 (31990855163) 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, 74243 + ... + 263616.

It is an arithmetic number, because the mean of its divisors is an integer number (7997821920).

Almost surely, 2^31990855133 is an apocalyptic number.

It is an amenable number.

31990855133 is a deficient number, since it is larger than the sum of its proper divisors (432547).

31990855133 is an equidigital number, since it uses as much as digits as its factorization.

31990855133 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 432546.

The product of its (nonzero) digits is 437400, while the sum is 47.

The spelling of 31990855133 in words is "thirty-one billion, nine hundred ninety million, eight hundred fifty-five thousand, one hundred thirty-three".