21348172 has 12 divisors (see below), whose sum is σ = 39325720. Its totient is φ = 10112256.

The previous prime is 21348161. The next prime is 21348203. The reversal of 21348172 is 27184312.

It is a self number, because there is not a number n which added to its sum of digits gives 21348172.

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, 140373 + ... + 140524.

Almost surely, 2^21348172 is an apocalyptic number.

It is an amenable number.

21348172 is a deficient number, since it is larger than the sum of its proper divisors (17977548).

21348172 is a wasteful number, since it uses less digits than its factorization.

21348172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 280920 (or 280918 counting only the distinct ones).

The product of its digits is 2688, while the sum is 28.

The square root of 21348172 is about 4620.4082070743. The cubic root of 21348172 is about 277.4087983172.

The spelling of 21348172 in words is "twenty-one million, three hundred forty-eight thousand, one hundred seventy-two".