665172615761 has 8 divisors (see below), whose sum is σ = 674555182848. Its totient is φ = 655790436000.

The previous prime is 665172615697. The next prime is 665172615773. The reversal of 665172615761 is 167516271566.

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 665172615761 - 2⁶ = 665172615697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (665172615461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6758696 + ... + 6856406.

It is an arithmetic number, because the mean of its divisors is an integer number (84319397856).

Almost surely, 2^665172615761 is an apocalyptic number.

It is an amenable number.

665172615761 is a deficient number, since it is larger than the sum of its proper divisors (9382567087).

665172615761 is an equidigital number, since it uses as much as digits as its factorization.

665172615761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 193663.

The product of its digits is 3175200, while the sum is 53.

The spelling of 665172615761 in words is "six hundred sixty-five billion, one hundred seventy-two million, six hundred fifteen thousand, seven hundred sixty-one".