21775365 has 32 divisors (see below), whose sum is σ = 40400640. Its totient is φ = 11107008.

The previous prime is 21775357. The next prime is 21775379. The reversal of 21775365 is 56357712.

It is not a de Polignac number, because 21775365 - 2³ = 21775357 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 402 + ... + 6611.

It is an arithmetic number, because the mean of its divisors is an integer number (1262520).

Almost surely, 2^21775365 is an apocalyptic number.

It is an amenable number.

21775365 is a deficient number, since it is larger than the sum of its proper divisors (18625275).

21775365 is a wasteful number, since it uses less digits than its factorization.

21775365 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7050 (or 7044 counting only the distinct ones).

The product of its digits is 44100, while the sum is 36.

The square root of 21775365 is about 4666.4081476013. The cubic root of 21775365 is about 279.2469775127.

The spelling of 21775365 in words is "twenty-one million, seven hundred seventy-five thousand, three hundred sixty-five".