21122410645 has 24 divisors (see below), whose sum is σ = 29493342648. Its totient is φ = 14479920000.

The previous prime is 21122410613. The next prime is 21122410651. The reversal of 21122410645 is 54601422112.

It can be written as a sum of positive squares in 4 ways, for example, as 5235824881 + 15886585764 = 72359^2 + 126042^2 .

It is not a de Polignac number, because 21122410645 - 2⁵ = 21122410613 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1073395 + ... + 1092895.

It is an arithmetic number, because the mean of its divisors is an integer number (1228889277).

Almost surely, 2^21122410645 is an apocalyptic number.

It is an amenable number.

21122410645 is a deficient number, since it is larger than the sum of its proper divisors (8370932003).

21122410645 is a wasteful number, since it uses less digits than its factorization.

21122410645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23941 (or 23934 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 28.

Adding to 21122410645 its reverse (54601422112), we get a palindrome (75723832757).

The spelling of 21122410645 in words is "twenty-one billion, one hundred twenty-two million, four hundred ten thousand, six hundred forty-five".