36865636921 has 2 divisors, whose sum is σ = 36865636922. Its totient is φ = 36865636920.

The previous prime is 36865636919. The next prime is 36865636931. The reversal of 36865636921 is 12963656863.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28489726521 + 8375910400 = 168789^2 + 91520^2 .

It is a cyclic number.

It is not a de Polignac number, because 36865636921 - 2¹ = 36865636919 is a prime.

Together with 36865636919, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (36865636931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18432818460 + 18432818461.

It is an arithmetic number, because the mean of its divisors is an integer number (18432818461).

Almost surely, 2^36865636921 is an apocalyptic number.

It is an amenable number.

36865636921 is a deficient number, since it is larger than the sum of its proper divisors (1).

36865636921 is an equidigital number, since it uses as much as digits as its factorization.

36865636921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8398080, while the sum is 55.

The spelling of 36865636921 in words is "thirty-six billion, eight hundred sixty-five million, six hundred thirty-six thousand, nine hundred twenty-one".