665902641 has 8 divisors (see below), whose sum is σ = 888750720. Its totient is φ = 443494832.

The previous prime is 665902603. The next prime is 665902649. The reversal of 665902641 is 146209566.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 665902641 - 2⁹ = 665902129 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 665902641.

It is not an unprimeable number, because it can be changed into a prime (665902649) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 106521 + ... + 112598.

It is an arithmetic number, because the mean of its divisors is an integer number (111093840).

Almost surely, 2^665902641 is an apocalyptic number.

It is an amenable number.

665902641 is a deficient number, since it is larger than the sum of its proper divisors (222848079).

665902641 is a wasteful number, since it uses less digits than its factorization.

665902641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220135.

The product of its (nonzero) digits is 77760, while the sum is 39.

The square root of 665902641 is about 25805.0894398760. The cubic root of 665902641 is about 873.2466182217.

The spelling of 665902641 in words is "six hundred sixty-five million, nine hundred two thousand, six hundred forty-one".