665046261 has 16 divisors (see below), whose sum is σ = 1074822720. Its totient is φ = 403058160.

The previous prime is 665046257. The next prime is 665046269. The reversal of 665046261 is 162640566.

It is a happy number.

It is not a de Polignac number, because 665046261 - 2² = 665046257 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665046269) 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, 1119310 + ... + 1119903.

It is an arithmetic number, because the mean of its divisors is an integer number (67176420).

Almost surely, 2^665046261 is an apocalyptic number.

It is an amenable number.

665046261 is a deficient number, since it is larger than the sum of its proper divisors (409776459).

665046261 is a wasteful number, since it uses less digits than its factorization.

665046261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2239233 (or 2239227 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The square root of 665046261 is about 25788.4908631738. The cubic root of 665046261 is about 872.8721131498.

The spelling of 665046261 in words is "six hundred sixty-five million, forty-six thousand, two hundred sixty-one".