21031270591 has 2 divisors, whose sum is σ = 21031270592. Its totient is φ = 21031270590.

The previous prime is 21031270553. The next prime is 21031270613. The reversal of 21031270591 is 19507213012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21031270591 - 2³³ = 12441335999 is a prime.

It is a super-2 number, since 2×21031270591² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21031270291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10515635295 + 10515635296.

It is an arithmetic number, because the mean of its divisors is an integer number (10515635296).

Almost surely, 2^21031270591 is an apocalyptic number.

21031270591 is a deficient number, since it is larger than the sum of its proper divisors (1).

21031270591 is an equidigital number, since it uses as much as digits as its factorization.

21031270591 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3780, while the sum is 31.

The spelling of 21031270591 in words is "twenty-one billion, thirty-one million, two hundred seventy thousand, five hundred ninety-one".