665046961 has 4 divisors (see below), whose sum is σ = 665145124. Its totient is φ = 664948800.

The previous prime is 665046947. The next prime is 665046973. The reversal of 665046961 is 169640566.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 274233600 + 390813361 = 16560^2 + 19769^2 .

It is a cyclic number.

It is not a de Polignac number, because 665046961 - 2¹³ = 665038769 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (665046061) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38100 + ... + 52741.

It is an arithmetic number, because the mean of its divisors is an integer number (166286281).

Almost surely, 2^665046961 is an apocalyptic number.

It is an amenable number.

665046961 is a deficient number, since it is larger than the sum of its proper divisors (98163).

665046961 is an equidigital number, since it uses as much as digits as its factorization.

665046961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98162.

The product of its (nonzero) digits is 233280, while the sum is 43.

The square root of 665046961 is about 25788.5044351160. The cubic root of 665046961 is about 872.8724193993.

The spelling of 665046961 in words is "six hundred sixty-five million, forty-six thousand, nine hundred sixty-one".