21357699966751 has 2 divisors, whose sum is σ = 21357699966752. Its totient is φ = 21357699966750.

The previous prime is 21357699966683. The next prime is 21357699966791. The reversal of 21357699966751 is 15766999675312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21357699966751 - 2²³ = 21357691578143 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21357699966791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10678849983375 + 10678849983376.

It is an arithmetic number, because the mean of its divisors is an integer number (10678849983376).

Almost surely, 2^{21357699966751} is an apocalyptic number.

21357699966751 is a deficient number, since it is larger than the sum of its proper divisors (1).

21357699966751 is an equidigital number, since it uses as much as digits as its factorization.

21357699966751 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1157360400, while the sum is 76.

The spelling of 21357699966751 in words is "twenty-one trillion, three hundred fifty-seven billion, six hundred ninety-nine million, nine hundred sixty-six thousand, seven hundred fifty-one".