20165580 has 36 divisors (see below), whose sum is σ = 61169472. Its totient is φ = 5377440.

The previous prime is 20165567. The next prime is 20165609. The reversal of 20165580 is 8556102.

20165580 is a `hidden beast` number, since 2 + 0 + 1 + 655 + 8 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 55836 + ... + 56195.

It is an arithmetic number, because the mean of its divisors is an integer number (1699152).

Almost surely, 2^20165580 is an apocalyptic number.

20165580 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20165580 is an abundant number, since it is smaller than the sum of its proper divisors (41003892).

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

20165580 is a wasteful number, since it uses less digits than its factorization.

20165580 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112046 (or 112041 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 27.

The square root of 20165580 is about 4490.6102035247. The cubic root of 20165580 is about 272.1887926617.

It can be divided in two parts, 20 and 165580, that added together give a triangular number (165600 = T₅₇₅).

The spelling of 20165580 in words is "twenty million, one hundred sixty-five thousand, five hundred eighty".