665777607331 has 4 divisors (see below), whose sum is σ = 665797204072. Its totient is φ = 665758010592.

The previous prime is 665777607323. The next prime is 665777607337. The reversal of 665777607331 is 133706777566.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 133706777566 = 2 ⋅66853388783.

It is a cyclic number.

It is not a de Polignac number, because 665777607331 - 2³ = 665777607323 is a prime.

It is a super-2 number, since 2×665777607331² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (665777607337) 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, 9747321 + ... + 9815386.

It is an arithmetic number, because the mean of its divisors is an integer number (166449301018).

Almost surely, 2^665777607331 is an apocalyptic number.

665777607331 is a deficient number, since it is larger than the sum of its proper divisors (19596741).

665777607331 is a wasteful number, since it uses less digits than its factorization.

665777607331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19596740.

The product of its (nonzero) digits is 23337720, while the sum is 58.

The spelling of 665777607331 in words is "six hundred sixty-five billion, seven hundred seventy-seven million, six hundred seven thousand, three hundred thirty-one".