21459116377 has 2 divisors, whose sum is σ = 21459116378. Its totient is φ = 21459116376.

The previous prime is 21459116359. The next prime is 21459116389. The reversal of 21459116377 is 77361195412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12478900681 + 8980215696 = 111709^2 + 94764^2 .

It is a cyclic number.

It is not a de Polignac number, because 21459116377 - 2²³ = 21450727769 is a prime.

It is a super-2 number, since 2×21459116377² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21459119377) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10729558188 + 10729558189.

It is an arithmetic number, because the mean of its divisors is an integer number (10729558189).

Almost surely, 2^21459116377 is an apocalyptic number.

It is an amenable number.

21459116377 is a deficient number, since it is larger than the sum of its proper divisors (1).

21459116377 is an equidigital number, since it uses as much as digits as its factorization.

21459116377 is an evil number, because the sum of its binary digits is even.

The product of its digits is 317520, while the sum is 46.

The spelling of 21459116377 in words is "twenty-one billion, four hundred fifty-nine million, one hundred sixteen thousand, three hundred seventy-seven".