21106028 has 12 divisors (see below), whose sum is σ = 37456272. Its totient is φ = 10404240.

The previous prime is 21105977. The next prime is 21106037. The reversal of 21106028 is 82060112.

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, 36875 + ... + 37442.

It is an arithmetic number, because the mean of its divisors is an integer number (3121356).

Almost surely, 2^21106028 is an apocalyptic number.

It is an amenable number.

21106028 is a deficient number, since it is larger than the sum of its proper divisors (16350244).

21106028 is a wasteful number, since it uses less digits than its factorization.

21106028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74392 (or 74390 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 20.

The square root of 21106028 is about 4594.1297326044. The cubic root of 21106028 is about 276.3559609348.

The spelling of 21106028 in words is "twenty-one million, one hundred six thousand, twenty-eight".