21310553509967 has 2 divisors, whose sum is σ = 21310553509968. Its totient is φ = 21310553509966.

The previous prime is 21310553509943. The next prime is 21310553510017. The reversal of 21310553509967 is 76990535501312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21310553509967 - 2³⁸ = 21035675603023 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21310553509067) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10655276754983 + 10655276754984.

It is an arithmetic number, because the mean of its divisors is an integer number (10655276754984).

Almost surely, 2^{21310553509967} is an apocalyptic number.

21310553509967 is a deficient number, since it is larger than the sum of its proper divisors (1).

21310553509967 is an equidigital number, since it uses as much as digits as its factorization.

21310553509967 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7654500, while the sum is 56.

The spelling of 21310553509967 in words is "twenty-one trillion, three hundred ten billion, five hundred fifty-three million, five hundred nine thousand, nine hundred sixty-seven".