21632265 has 40 divisors (see below), whose sum is σ = 40051968. Its totient is φ = 11158560.

The previous prime is 21632257. The next prime is 21632287. The reversal of 21632265 is 56223612.

21632265 is a `hidden beast` number, since 2 + 1 + 632 + 26 + 5 = 666.

It is not a de Polignac number, because 21632265 - 2³ = 21632257 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 11694 + ... + 13416.

Almost surely, 2^21632265 is an apocalyptic number.

It is an amenable number.

21632265 is a deficient number, since it is larger than the sum of its proper divisors (18419703).

21632265 is a wasteful number, since it uses less digits than its factorization.

21632265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1771 (or 1762 counting only the distinct ones).

The product of its digits is 4320, while the sum is 27.

The square root of 21632265 is about 4651.0498814784. The cubic root of 21632265 is about 278.6339284956.

Adding to 21632265 its reverse (56223612), we get a palindrome (77855877).

The spelling of 21632265 in words is "twenty-one million, six hundred thirty-two thousand, two hundred sixty-five".