21612493596931 has 2 divisors, whose sum is σ = 21612493596932. Its totient is φ = 21612493596930.

The previous prime is 21612493596913. The next prime is 21612493596961. The reversal of 21612493596931 is 13969539421612.

Together with previous prime (21612493596913) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21612493596931 - 2¹¹ = 21612493594883 is a prime.

It is a super-2 number, since 2×21612493596931² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21612493596931.

It is not a weakly prime, because it can be changed into another prime (21612493596961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10806246798465 + 10806246798466.

It is an arithmetic number, because the mean of its divisors is an integer number (10806246798466).

Almost surely, 2^{21612493596931} is an apocalyptic number.

21612493596931 is a deficient number, since it is larger than the sum of its proper divisors (1).

21612493596931 is an equidigital number, since it uses as much as digits as its factorization.

21612493596931 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18895680, while the sum is 61.

The spelling of 21612493596931 in words is "twenty-one trillion, six hundred twelve billion, four hundred ninety-three million, five hundred ninety-six thousand, nine hundred thirty-one".