665212251520331 has 4 divisors (see below), whose sum is σ = 700223422653000. Its totient is φ = 630201080387664.

The previous prime is 665212251520309. The next prime is 665212251520361. The reversal of 665212251520331 is 133025152212566.

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

It is a cyclic number.

It is not a de Polignac number, because 665212251520331 - 2⁴² = 660814205009227 is a prime.

It is a super-2 number, since 2×665212251520331² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (665212251520361) 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, 17505585566306 + ... + 17505585566343.

It is an arithmetic number, because the mean of its divisors is an integer number (175055855663250).

Almost surely, 2^{665212251520331} is an apocalyptic number.

665212251520331 is a deficient number, since it is larger than the sum of its proper divisors (35011171132669).

665212251520331 is a wasteful number, since it uses less digits than its factorization.

665212251520331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35011171132668.

The product of its (nonzero) digits is 648000, while the sum is 44.

The spelling of 665212251520331 in words is "six hundred sixty-five trillion, two hundred twelve billion, two hundred fifty-one million, five hundred twenty thousand, three hundred thirty-one".