20165705 has 24 divisors (see below), whose sum is σ = 28699272. Its totient is φ = 13558272.

The previous prime is 20165693. The next prime is 20165713. The reversal of 20165705 is 50756102.

It can be written as a sum of positive squares in 4 ways, for example, as 840889 + 19324816 = 917^2 + 4396^2 .

It is not a de Polignac number, because 20165705 - 2⁸ = 20165449 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12209 + ... + 13761.

It is an arithmetic number, because the mean of its divisors is an integer number (1195803).

Almost surely, 2^20165705 is an apocalyptic number.

It is an amenable number.

20165705 is a deficient number, since it is larger than the sum of its proper divisors (8533567).

20165705 is a wasteful number, since it uses less digits than its factorization.

20165705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1625 (or 1618 counting only the distinct ones).

The product of its (nonzero) digits is 2100, while the sum is 26.

The square root of 20165705 is about 4490.6241214335. The cubic root of 20165705 is about 272.1893550644.

The spelling of 20165705 in words is "twenty million, one hundred sixty-five thousand, seven hundred five".