20187172 has 12 divisors (see below), whose sum is σ = 35513856. Its totient is φ = 10040360.

The previous prime is 20187151. The next prime is 20187191. The reversal of 20187172 is 27178102.

It is a self number, because there is not a number n which added to its sum of digits gives 20187172.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12448 + ... + 13975.

It is an arithmetic number, because the mean of its divisors is an integer number (2959488).

Almost surely, 2^20187172 is an apocalyptic number.

It is an amenable number.

20187172 is a deficient number, since it is larger than the sum of its proper divisors (15326684).

20187172 is a wasteful number, since it uses less digits than its factorization.

20187172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26618 (or 26616 counting only the distinct ones).

The product of its (nonzero) digits is 1568, while the sum is 28.

The square root of 20187172 is about 4493.0136879382. The cubic root of 20187172 is about 272.2859053996.

The spelling of 20187172 in words is "twenty million, one hundred eighty-seven thousand, one hundred seventy-two".