20628690 has 16 divisors (see below), whose sum is σ = 49508928. Its totient is φ = 5500976.

The previous prime is 20628683. The next prime is 20628709. The reversal of 20628690 is 9682602.

It is a super-2 number, since 2×20628690² = 851085702232200, which contains 22 as substring.

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, 343782 + ... + 343841.

It is an arithmetic number, because the mean of its divisors is an integer number (3094308).

Almost surely, 2^20628690 is an apocalyptic number.

20628690 is an abundant number, since it is smaller than the sum of its proper divisors (28880238).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20628690 is a wasteful number, since it uses less digits than its factorization.

20628690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 687633.

The product of its (nonzero) digits is 10368, while the sum is 33.

The square root of 20628690 is about 4541.8817686065. The cubic root of 20628690 is about 274.2566813423.

The spelling of 20628690 in words is "twenty million, six hundred twenty-eight thousand, six hundred ninety".