20188644 has 24 divisors (see below), whose sum is σ = 53836608. Its totient is φ = 5768160.

The previous prime is 20188633. The next prime is 20188667. The reversal of 20188644 is 44688102.

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, 120087 + ... + 120254.

It is an arithmetic number, because the mean of its divisors is an integer number (2243192).

Almost surely, 2^20188644 is an apocalyptic number.

It is an amenable number.

20188644 is an abundant number, since it is smaller than the sum of its proper divisors (33647964).

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

20188644 is a wasteful number, since it uses less digits than its factorization.

20188644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 240355 (or 240353 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 33.

The square root of 20188644 is about 4493.1774948248. The cubic root of 20188644 is about 272.2925233830.

It can be divided in two parts, 201886 and 44, that added together give a triangular number (201930 = T₆₃₅).

The spelling of 20188644 in words is "twenty million, one hundred eighty-eight thousand, six hundred forty-four".