20565166 has 16 divisors (see below), whose sum is σ = 31691088. Its totient is φ = 10004800.

The previous prime is 20565157. The next prime is 20565169. The reversal of 20565166 is 66156502.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20565169) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13146 + ... + 14626.

It is an arithmetic number, because the mean of its divisors is an integer number (1980693).

Almost surely, 2^20565166 is an apocalyptic number.

20565166 is a deficient number, since it is larger than the sum of its proper divisors (11125922).

20565166 is a wasteful number, since it uses less digits than its factorization.

20565166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1667.

The product of its (nonzero) digits is 10800, while the sum is 31.

The square root of 20565166 is about 4534.8832399523. The cubic root of 20565166 is about 273.9748764859.

The spelling of 20565166 in words is "twenty million, five hundred sixty-five thousand, one hundred sixty-six".