21577864459 has 2 divisors, whose sum is σ = 21577864460. Its totient is φ = 21577864458.

The previous prime is 21577864411. The next prime is 21577864481. The reversal of 21577864459 is 95446877512.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21577864459 - 2⁷ = 21577864331 is a prime.

It is a super-2 number, since 2×21577864459² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21577814459) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10788932229 + 10788932230.

It is an arithmetic number, because the mean of its divisors is an integer number (10788932230).

Almost surely, 2^21577864459 is an apocalyptic number.

21577864459 is a deficient number, since it is larger than the sum of its proper divisors (1).

21577864459 is an equidigital number, since it uses as much as digits as its factorization.

21577864459 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16934400, while the sum is 58.

The spelling of 21577864459 in words is "twenty-one billion, five hundred seventy-seven million, eight hundred sixty-four thousand, four hundred fifty-nine".