22505640 has 32 divisors (see below), whose sum is σ = 67517280. Its totient is φ = 6001472.

The previous prime is 22505627. The next prime is 22505663. The reversal of 22505640 is 4650522.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 22505640.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 93654 + ... + 93893.

It is an arithmetic number, because the mean of its divisors is an integer number (2109915).

Almost surely, 2^22505640 is an apocalyptic number.

22505640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

22505640 is an abundant number, since it is smaller than the sum of its proper divisors (45011640).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

22505640 is a wasteful number, since it uses less digits than its factorization.

22505640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187561 (or 187557 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 24.

The square root of 22505640 is about 4744.0109612015. The cubic root of 22505640 is about 282.3343953301.

The spelling of 22505640 in words is "twenty-two million, five hundred five thousand, six hundred forty".