20936556 has 90 divisors (see below), whose sum is σ = 58087260. Its totient is φ = 6574608.

The previous prime is 20936549. The next prime is 20936567. The reversal of 20936556 is 65563902.

It is a super-2 number, since 2×20936556² = 876678754282272, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 20936556.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 116875 + ... + 117053.

It is an arithmetic number, because the mean of its divisors is an integer number (645414).

Almost surely, 2^20936556 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20936556, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29043630).

20936556 is an abundant number, since it is smaller than the sum of its proper divisors (37150704).

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

20936556 is a wasteful number, since it uses less digits than its factorization.

20936556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 233 (or 203 counting only the distinct ones).

The product of its (nonzero) digits is 48600, while the sum is 36.

The square root of 20936556 is about 4575.6481508088. The cubic root of 20936556 is about 275.6143005704.

It can be divided in two parts, 2093 and 6556, that added together give a square (8649 = 93²).

The spelling of 20936556 in words is "twenty million, nine hundred thirty-six thousand, five hundred fifty-six".