1665500565 has 32 divisors (see below), whose sum is σ = 2738727936. Its totient is φ = 863767040.

The previous prime is 1665500549. The next prime is 1665500581. The reversal of 1665500565 is 5650055661.

It is an interprime number because it is at equal distance from previous prime (1665500549) and next prime (1665500581).

It is not a de Polignac number, because 1665500565 - 2⁴ = 1665500549 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 190684 + ... + 199226.

It is an arithmetic number, because the mean of its divisors is an integer number (85585248).

Almost surely, 2^1665500565 is an apocalyptic number.

1665500565 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1665500565 is a deficient number, since it is larger than the sum of its proper divisors (1073227371).

1665500565 is a wasteful number, since it uses less digits than its factorization.

1665500565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8909.

The product of its (nonzero) digits is 135000, while the sum is 39.

The square root of 1665500565 is about 40810.5447770549. The cubic root of 1665500565 is about 1185.3545237024.

The spelling of 1665500565 in words is "one billion, six hundred sixty-five million, five hundred thousand, five hundred sixty-five".