20642556 has 48 divisors (see below), whose sum is σ = 55641600. Its totient is φ = 5886720.

The previous prime is 20642527. The next prime is 20642561. The reversal of 20642556 is 65524602.

It is a super-2 number, since 2×20642556² = 852230236426272, which contains 22 as substring.

It is a congruent number.

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 15 ways as a sum of consecutive naturals, for example, 2356 + ... + 6843.

It is an arithmetic number, because the mean of its divisors is an integer number (1159200).

Almost surely, 2^20642556 is an apocalyptic number.

It is an amenable number.

20642556 is an abundant number, since it is smaller than the sum of its proper divisors (34999044).

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

20642556 is a wasteful number, since it uses less digits than its factorization.

20642556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9234 (or 9232 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 30.

The square root of 20642556 is about 4543.4079719964. The cubic root of 20642556 is about 274.3181166767.

The spelling of 20642556 in words is "twenty million, six hundred forty-two thousand, five hundred fifty-six".