21031159931 has 2 divisors, whose sum is σ = 21031159932. Its totient is φ = 21031159930.

The previous prime is 21031159859. The next prime is 21031159939. The reversal of 21031159931 is 13995113012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21031159931 - 2²⁶ = 20964051067 is a prime.

It is a super-2 number, since 2×21031159931² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21031159891 and 21031159900.

It is not a weakly prime, because it can be changed into another prime (21031159939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10515579965 + 10515579966.

It is an arithmetic number, because the mean of its divisors is an integer number (10515579966).

Almost surely, 2^21031159931 is an apocalyptic number.

21031159931 is a deficient number, since it is larger than the sum of its proper divisors (1).

21031159931 is an equidigital number, since it uses as much as digits as its factorization.

21031159931 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7290, while the sum is 35.

The spelling of 21031159931 in words is "twenty-one billion, thirty-one million, one hundred fifty-nine thousand, nine hundred thirty-one".