36815781561 has 16 divisors (see below), whose sum is σ = 54686573760. Its totient is φ = 21874628160.

The previous prime is 36815781557. The next prime is 36815781571. The reversal of 36815781561 is 16518751863.

It is not a de Polignac number, because 36815781561 - 2² = 36815781557 is a prime.

It is not an unprimeable number, because it can be changed into a prime (36815781571) 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 15 ways as a sum of consecutive naturals, for example, 16274635 + ... + 16276896.

It is an arithmetic number, because the mean of its divisors is an integer number (3417910860).

Almost surely, 2^36815781561 is an apocalyptic number.

It is an amenable number.

36815781561 is a deficient number, since it is larger than the sum of its proper divisors (17870792199).

36815781561 is a wasteful number, since it uses less digits than its factorization.

36815781561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32551576.

The product of its digits is 1209600, while the sum is 51.

The spelling of 36815781561 in words is "thirty-six billion, eight hundred fifteen million, seven hundred eighty-one thousand, five hundred sixty-one".