666265605 has 16 divisors (see below), whose sum is σ = 1073088384. Its totient is φ = 352987200.

The previous prime is 666265603. The next prime is 666265643. The reversal of 666265605 is 506562666.

It is not a de Polignac number, because 666265605 - 2¹ = 666265603 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666265601) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 144814 + ... + 149343.

It is an arithmetic number, because the mean of its divisors is an integer number (67068024).

Almost surely, 2^666265605 is an apocalyptic number.

It is an amenable number.

666265605 is a deficient number, since it is larger than the sum of its proper divisors (406822779).

666265605 is a wasteful number, since it uses less digits than its factorization.

666265605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 294316.

The product of its (nonzero) digits is 388800, while the sum is 42.

The square root of 666265605 is about 25812.1212805147. The cubic root of 666265605 is about 873.4052497770.

The spelling of 666265605 in words is "six hundred sixty-six million, two hundred sixty-five thousand, six hundred five".