21662925 has 12 divisors (see below), whose sum is σ = 35816160. Its totient is φ = 11553520.

The previous prime is 21662923. The next prime is 21662929. The reversal of 21662925 is 52926612.

It is not a de Polignac number, because 21662925 - 2¹ = 21662923 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21662923) 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, 144345 + ... + 144494.

It is an arithmetic number, because the mean of its divisors is an integer number (2984680).

Almost surely, 2^21662925 is an apocalyptic number.

21662925 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21662925 is a deficient number, since it is larger than the sum of its proper divisors (14153235).

21662925 is a wasteful number, since it uses less digits than its factorization.

21662925 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 288852 (or 288847 counting only the distinct ones).

The product of its digits is 12960, while the sum is 33.

The square root of 21662925 is about 4654.3447444297. The cubic root of 21662925 is about 278.7655048452.

The spelling of 21662925 in words is "twenty-one million, six hundred sixty-two thousand, nine hundred twenty-five".