21110102621 has 2 divisors, whose sum is σ = 21110102622. Its totient is φ = 21110102620.

The previous prime is 21110102579. The next prime is 21110102641. The reversal of 21110102621 is 12620101112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13346025625 + 7764076996 = 115525^2 + 88114^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21110102621 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21110102621.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21110102641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555051310 + 10555051311.

It is an arithmetic number, because the mean of its divisors is an integer number (10555051311).

Almost surely, 2^21110102621 is an apocalyptic number.

It is an amenable number.

21110102621 is a deficient number, since it is larger than the sum of its proper divisors (1).

21110102621 is an equidigital number, since it uses as much as digits as its factorization.

21110102621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48, while the sum is 17.

Adding to 21110102621 its reverse (12620101112), we get a palindrome (33730203733).

The spelling of 21110102621 in words is "twenty-one billion, one hundred ten million, one hundred two thousand, six hundred twenty-one".