20665315 has 16 divisors (see below), whose sum is σ = 27141120. Its totient is φ = 14980320.

The previous prime is 20665297. The next prime is 20665357. The reversal of 20665315 is 51356602.

It is a de Polignac number, because none of the positive numbers 2^k-20665315 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33076 + ... + 33694.

It is an arithmetic number, because the mean of its divisors is an integer number (1696320).

Almost surely, 2^20665315 is an apocalyptic number.

20665315 is a deficient number, since it is larger than the sum of its proper divisors (6475805).

20665315 is a wasteful number, since it uses less digits than its factorization.

20665315 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1242.

The product of its (nonzero) digits is 5400, while the sum is 28.

The square root of 20665315 is about 4545.9118997183. The cubic root of 20665315 is about 274.4188941351.

It can be divided in two parts, 2066 and 5315, that added together give a triangular number (7381 = T₁₂₁).

The spelling of 20665315 in words is "twenty million, six hundred sixty-five thousand, three hundred fifteen".