21450450645 has 64 divisors (see below), whose sum is σ = 41099788800. Its totient is φ = 10551928320.

The previous prime is 21450450617. The next prime is 21450450701. The reversal of 21450450645 is 54605405412.

21450450645 is a `hidden beast` number, since 2 + 1 + 4 + 5 + 0 + 4 + 5 + 0 + 645 = 666.

It is not a de Polignac number, because 21450450645 - 2⁷ = 21450450517 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2647761 + ... + 2655849.

It is an arithmetic number, because the mean of its divisors is an integer number (642184200).

Almost surely, 2^21450450645 is an apocalyptic number.

It is an amenable number.

21450450645 is a deficient number, since it is larger than the sum of its proper divisors (19649338155).

21450450645 is a wasteful number, since it uses less digits than its factorization.

21450450645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9627 (or 9621 counting only the distinct ones).

The product of its (nonzero) digits is 96000, while the sum is 36.

The spelling of 21450450645 in words is "twenty-one billion, four hundred fifty million, four hundred fifty thousand, six hundred forty-five".