20345021631 has 12 divisors (see below), whose sum is σ = 32058822120. Its totient is φ = 12330316080.

The previous prime is 20345021603. The next prime is 20345021701. The reversal of 20345021631 is 13612054302.

20345021631 is a `hidden beast` number, since 2 + 0 + 3 + 4 + 5 + 0 + 21 + 631 = 666.

It is not a de Polignac number, because 20345021631 - 2¹⁵ = 20344988863 is a prime.

It is a super-2 number, since 2×20345021631² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20345021595 and 20345021604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20345021531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 102752536 + ... + 102752733.

It is an arithmetic number, because the mean of its divisors is an integer number (2671568510).

Almost surely, 2^20345021631 is an apocalyptic number.

20345021631 is a deficient number, since it is larger than the sum of its proper divisors (11713800489).

20345021631 is a wasteful number, since it uses less digits than its factorization.

20345021631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 205505286 (or 205505283 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

Adding to 20345021631 its reverse (13612054302), we get a palindrome (33957075933).

The spelling of 20345021631 in words is "twenty billion, three hundred forty-five million, twenty-one thousand, six hundred thirty-one".