665867587121 has 8 divisors (see below), whose sum is σ = 727279370784. Its totient is φ = 604602197920.

The previous prime is 665867587117. The next prime is 665867587127. The reversal of 665867587121 is 121785768566.

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 665867587121 - 2² = 665867587117 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (665867587127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36589100 + ... + 36607293.

It is an arithmetic number, because the mean of its divisors is an integer number (90909921348).

Almost surely, 2^665867587121 is an apocalyptic number.

It is an amenable number.

665867587121 is a deficient number, since it is larger than the sum of its proper divisors (61411783663).

665867587121 is a wasteful number, since it uses less digits than its factorization.

665867587121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73197231.

The product of its digits is 33868800, while the sum is 62.

The spelling of 665867587121 in words is "six hundred sixty-five billion, eight hundred sixty-seven million, five hundred eighty-seven thousand, one hundred twenty-one".