21222235062521 has 2 divisors, whose sum is σ = 21222235062522. Its totient is φ = 21222235062520.

The previous prime is 21222235062499. The next prime is 21222235062593. The reversal of 21222235062521 is 12526053222212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20619445866496 + 602789196025 = 4540864^2 + 776395^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21222235062521 is a prime.

It is a super-2 number, since 2×21222235062521² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21222235052521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10611117531260 + 10611117531261.

It is an arithmetic number, because the mean of its divisors is an integer number (10611117531261).

Almost surely, 2^{21222235062521} is an apocalyptic number.

It is an amenable number.

21222235062521 is a deficient number, since it is larger than the sum of its proper divisors (1).

21222235062521 is an equidigital number, since it uses as much as digits as its factorization.

21222235062521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 57600, while the sum is 35.

Adding to 21222235062521 its reverse (12526053222212), we get a palindrome (33748288284733).

The spelling of 21222235062521 in words is "twenty-one trillion, two hundred twenty-two billion, two hundred thirty-five million, sixty-two thousand, five hundred twenty-one".