660673641 has 4 divisors (see below), whose sum is σ = 880898192. Its totient is φ = 440449092.

The previous prime is 660673633. The next prime is 660673649. The reversal of 660673641 is 146376066.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (660673633) and next prime (660673649).

It is not a de Polignac number, because 660673641 - 2³ = 660673633 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 660673641.

It is not an unprimeable number, because it can be changed into a prime (660673649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 110112271 + ... + 110112276.

It is an arithmetic number, because the mean of its divisors is an integer number (220224548).

Almost surely, 2^660673641 is an apocalyptic number.

It is an amenable number.

660673641 is a deficient number, since it is larger than the sum of its proper divisors (220224551).

660673641 is a wasteful number, since it uses less digits than its factorization.

660673641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 220224550.

The product of its (nonzero) digits is 108864, while the sum is 39.

The square root of 660673641 is about 25703.5725337938. The cubic root of 660673641 is about 870.9548862954.

The spelling of 660673641 in words is "six hundred sixty million, six hundred seventy-three thousand, six hundred forty-one".