21345328 has 20 divisors (see below), whose sum is σ = 41432368. Its totient is φ = 10653120.

The previous prime is 21345287. The next prime is 21345347. The reversal of 21345328 is 82354312.

It is a junction number, because it is equal to n+sod(n) for n = 21345296 and 21345305.

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, 12358 + ... + 13978.

Almost surely, 2^21345328 is an apocalyptic number.

It is an amenable number.

21345328 is a deficient number, since it is larger than the sum of its proper divisors (20087040).

21345328 is a wasteful number, since it uses less digits than its factorization.

21345328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2452 (or 2446 counting only the distinct ones).

The product of its digits is 5760, while the sum is 28.

The square root of 21345328 is about 4620.1004318088. The cubic root of 21345328 is about 277.3964789851.

The spelling of 21345328 in words is "twenty-one million, three hundred forty-five thousand, three hundred twenty-eight".