21325228 has 12 divisors (see below), whose sum is σ = 37604952. Its totient is φ = 10580960.

The previous prime is 21325219. The next prime is 21325279. The reversal of 21325228 is 82252312.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19825 + ... + 20872.

It is an arithmetic number, because the mean of its divisors is an integer number (3133746).

Almost surely, 2^21325228 is an apocalyptic number.

It is an amenable number.

21325228 is a deficient number, since it is larger than the sum of its proper divisors (16279724).

21325228 is a wasteful number, since it uses less digits than its factorization.

21325228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40832 (or 40830 counting only the distinct ones).

The product of its digits is 1920, while the sum is 25.

The square root of 21325228 is about 4617.9246420876. The cubic root of 21325228 is about 277.3093807644.

The spelling of 21325228 in words is "twenty-one million, three hundred twenty-five thousand, two hundred twenty-eight".