21323925 has 48 divisors (see below), whose sum is σ = 44778880. Its totient is φ = 9745920.

The previous prime is 21323893. The next prime is 21323941. The reversal of 21323925 is 52932312.

It is not a de Polignac number, because 21323925 - 2⁵ = 21323893 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 a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2469 + ... + 6981.

Almost surely, 2^21323925 is an apocalyptic number.

21323925 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21323925 is an abundant number, since it is smaller than the sum of its proper divisors (23454955).

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

21323925 is a wasteful number, since it uses less digits than its factorization.

21323925 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4539 (or 4528 counting only the distinct ones).

The product of its digits is 3240, while the sum is 27.

The square root of 21323925 is about 4617.7835592414. The cubic root of 21323925 is about 277.3037326578.

The spelling of 21323925 in words is "twenty-one million, three hundred twenty-three thousand, nine hundred twenty-five".