21223666526645 has 48 divisors (see below), whose sum is σ = 28080275577984. Its totient is φ = 15272353824000.

The previous prime is 21223666526551. The next prime is 21223666526677. The reversal of 21223666526645 is 54662566632212.

It is not a de Polignac number, because 21223666526645 - 2⁴² = 16825620015541 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 895992992 + ... + 896016678.

It is an arithmetic number, because the mean of its divisors is an integer number (585005741208).

Almost surely, 2^{21223666526645} is an apocalyptic number.

It is an amenable number.

21223666526645 is a deficient number, since it is larger than the sum of its proper divisors (6856609051339).

21223666526645 is a wasteful number, since it uses less digits than its factorization.

21223666526645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25502 (or 25401 counting only the distinct ones).

The product of its digits is 37324800, while the sum is 56.

The spelling of 21223666526645 in words is "twenty-one trillion, two hundred twenty-three billion, six hundred sixty-six million, five hundred twenty-six thousand, six hundred forty-five".