22615965821 has 2 divisors, whose sum is σ = 22615965822. Its totient is φ = 22615965820.

The previous prime is 22615965809. The next prime is 22615965859. The reversal of 22615965821 is 12856951622.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11593905625 + 11022060196 = 107675^2 + 104986^2 .

It is a cyclic number.

It is not a de Polignac number, because 22615965821 - 2¹⁰ = 22615964797 is a prime.

It is a super-2 number, since 2×22615965821² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22615961821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11307982910 + 11307982911.

It is an arithmetic number, because the mean of its divisors is an integer number (11307982911).

Almost surely, 2^22615965821 is an apocalyptic number.

It is an amenable number.

22615965821 is a deficient number, since it is larger than the sum of its proper divisors (1).

22615965821 is an equidigital number, since it uses as much as digits as its factorization.

22615965821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 518400, while the sum is 47.

The spelling of 22615965821 in words is "twenty-two billion, six hundred fifteen million, nine hundred sixty-five thousand, eight hundred twenty-one".