36961816681 has 16 divisors (see below), whose sum is σ = 37973368656. Its totient is φ = 35964000000.

The previous prime is 36961816637. The next prime is 36961816781. The reversal of 36961816681 is 18661816963.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 258920281 + 36702896400 = 16091^2 + 191580^2 .

It is a cyclic number.

It is not a de Polignac number, because 36961816681 - 2²⁵ = 36928262249 is a prime.

It is a super-2 number, since 2×36961816681² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (36961816601) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9985131 + ... + 9988831.

It is an arithmetic number, because the mean of its divisors is an integer number (2373335541).

Almost surely, 2^36961816681 is an apocalyptic number.

It is an amenable number.

36961816681 is a deficient number, since it is larger than the sum of its proper divisors (1011551975).

36961816681 is a wasteful number, since it uses less digits than its factorization.

36961816681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5484.

The product of its digits is 2239488, while the sum is 55.

The spelling of 36961816681 in words is "thirty-six billion, nine hundred sixty-one million, eight hundred sixteen thousand, six hundred eighty-one".