20556424 has 32 divisors (see below), whose sum is σ = 44222400. Its totient is φ = 8775360.

The previous prime is 20556409. The next prime is 20556433. The reversal of 20556424 is 42465502.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a junction number, because it is equal to n+sod(n) for n = 20556392 and 20556401.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17982 + ... + 19090.

It is an arithmetic number, because the mean of its divisors is an integer number (1381950).

Almost surely, 2^20556424 is an apocalyptic number.

It is an amenable number.

20556424 is an abundant number, since it is smaller than the sum of its proper divisors (23665976).

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

20556424 is a wasteful number, since it uses less digits than its factorization.

20556424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1453 (or 1449 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 28.

The square root of 20556424 is about 4533.9192758584. The cubic root of 20556424 is about 273.9360498632.

The spelling of 20556424 in words is "twenty million, five hundred fifty-six thousand, four hundred twenty-four".