21874925 has 12 divisors (see below), whose sum is σ = 27183156. Its totient is φ = 17462400.

The previous prime is 21874921. The next prime is 21874939. The reversal of 21874925 is 52947812.

It can be written as a sum of positive squares in 6 ways, for example, as 521284 + 21353641 = 722^2 + 4621^2 .

It is not a de Polignac number, because 21874925 - 2² = 21874921 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21874921) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20915 + ... + 21935.

It is an arithmetic number, because the mean of its divisors is an integer number (2265263).

Almost surely, 2^21874925 is an apocalyptic number.

21874925 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21874925 is a deficient number, since it is larger than the sum of its proper divisors (5308231).

21874925 is a wasteful number, since it uses less digits than its factorization.

21874925 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1888 (or 1883 counting only the distinct ones).

The product of its digits is 40320, while the sum is 38.

The square root of 21874925 is about 4677.0637156233. The cubic root of 21874925 is about 279.6719158946.

The spelling of 21874925 in words is "twenty-one million, eight hundred seventy-four thousand, nine hundred twenty-five".