665157164407361 has 4 divisors (see below), whose sum is σ = 665213017737300. Its totient is φ = 665101311077424.

The previous prime is 665157164407343. The next prime is 665157164407367. The reversal of 665157164407361 is 163704461751566.

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

It can be written as a sum of positive squares in 2 ways, for example, as 101173321665025 + 563983842742336 = 10058495^2 + 23748344^2 .

It is a cyclic number.

It is not a de Polignac number, because 665157164407361 - 2⁶ = 665157164407297 is a prime.

It is a super-2 number, since 2×665157164407361² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 665157164407294 and 665157164407303.

It is not an unprimeable number, because it can be changed into a prime (665157164407367) 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, 27926647106 + ... + 27926670923.

It is an arithmetic number, because the mean of its divisors is an integer number (166303254434325).

Almost surely, 2^{665157164407361} is an apocalyptic number.

It is an amenable number.

665157164407361 is a deficient number, since it is larger than the sum of its proper divisors (55853329939).

665157164407361 is a wasteful number, since it uses less digits than its factorization.

665157164407361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55853329938.

The product of its (nonzero) digits is 76204800, while the sum is 62.

The spelling of 665157164407361 in words is "six hundred sixty-five trillion, one hundred fifty-seven billion, one hundred sixty-four million, four hundred seven thousand, three hundred sixty-one".