20631939576251 has 2 divisors, whose sum is σ = 20631939576252. Its totient is φ = 20631939576250.

The previous prime is 20631939576181. The next prime is 20631939576307. The reversal of 20631939576251 is 15267593913602.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20631939576251 is a prime.

It is not a weakly prime, because it can be changed into another prime (20631939575251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10315969788125 + 10315969788126.

It is an arithmetic number, because the mean of its divisors is an integer number (10315969788126).

Almost surely, 2^{20631939576251} is an apocalyptic number.

20631939576251 is a deficient number, since it is larger than the sum of its proper divisors (1).

20631939576251 is an equidigital number, since it uses as much as digits as its factorization.

20631939576251 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18370800, while the sum is 59.

The spelling of 20631939576251 in words is "twenty trillion, six hundred thirty-one billion, nine hundred thirty-nine million, five hundred seventy-six thousand, two hundred fifty-one".