21725324 has 6 divisors (see below), whose sum is σ = 38019324. Its totient is φ = 10862660.

The previous prime is 21725309. The next prime is 21725351. The reversal of 21725324 is 42352712.

It is a junction number, because it is equal to n+sod(n) for n = 21725293 and 21725302.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2715662 + ... + 2715669.

It is an arithmetic number, because the mean of its divisors is an integer number (6336554).

Almost surely, 2^21725324 is an apocalyptic number.

It is an amenable number.

21725324 is a deficient number, since it is larger than the sum of its proper divisors (16294000).

21725324 is a wasteful number, since it uses less digits than its factorization.

21725324 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5431335 (or 5431333 counting only the distinct ones).

The product of its digits is 3360, while the sum is 26.

The square root of 21725324 is about 4661.0432308658. The cubic root of 21725324 is about 279.0329050830.

The spelling of 21725324 in words is "twenty-one million, seven hundred twenty-five thousand, three hundred twenty-four".