20890556 has 24 divisors (see below), whose sum is σ = 38352720. Its totient is φ = 9942912.

The previous prime is 20890511. The next prime is 20890579. The reversal of 20890556 is 65509802.

It is a congruent number.

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, 7235 + ... + 9701.

It is an arithmetic number, because the mean of its divisors is an integer number (1598030).

Almost surely, 2^20890556 is an apocalyptic number.

It is an amenable number.

20890556 is a deficient number, since it is larger than the sum of its proper divisors (17462164).

20890556 is a wasteful number, since it uses less digits than its factorization.

20890556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2573 (or 2571 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 35.

The square root of 20890556 is about 4570.6187764897. The cubic root of 20890556 is about 275.4123005476.

The spelling of 20890556 in words is "twenty million, eight hundred ninety thousand, five hundred fifty-six".