20928866 has 16 divisors (see below), whose sum is σ = 35939904. Its totient is φ = 8954064.

The previous prime is 20928851. The next prime is 20928871. The reversal of 20928866 is 66882902.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11516 + ... + 13208.

It is an arithmetic number, because the mean of its divisors is an integer number (2246244).

Almost surely, 2^20928866 is an apocalyptic number.

20928866 is a deficient number, since it is larger than the sum of its proper divisors (15011038).

20928866 is a wasteful number, since it uses less digits than its factorization.

20928866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2585.

The product of its (nonzero) digits is 82944, while the sum is 41.

The square root of 20928866 is about 4574.8077555237. The cubic root of 20928866 is about 275.5805520475.

The spelling of 20928866 in words is "twenty million, nine hundred twenty-eight thousand, eight hundred sixty-six".