21181282053577 has 2 divisors, whose sum is σ = 21181282053578. Its totient is φ = 21181282053576.

The previous prime is 21181282053563. The next prime is 21181282053619. The reversal of 21181282053577 is 77535028218112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20769703349641 + 411578703936 = 4557379^2 + 641544^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21181282053577 is a prime.

It is not a weakly prime, because it can be changed into another prime (21181282053377) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10590641026788 + 10590641026789.

It is an arithmetic number, because the mean of its divisors is an integer number (10590641026789).

Almost surely, 2^{21181282053577} is an apocalyptic number.

It is an amenable number.

21181282053577 is a deficient number, since it is larger than the sum of its proper divisors (1).

21181282053577 is an equidigital number, since it uses as much as digits as its factorization.

21181282053577 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1881600, while the sum is 52.

The spelling of 21181282053577 in words is "twenty-one trillion, one hundred eighty-one billion, two hundred eighty-two million, fifty-three thousand, five hundred seventy-seven".