11636905921 has 16 divisors (see below), whose sum is σ = 12074436864. Its totient is φ = 11207649024.

The previous prime is 11636905901. The next prime is 11636905957. The reversal of 11636905921 is 12950963611.

It is a cyclic number.

It is not a de Polignac number, because 11636905921 - 2⁷ = 11636905793 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11636905901) 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, 5897091 + ... + 5899063.

It is an arithmetic number, because the mean of its divisors is an integer number (754652304).

Almost surely, 2^11636905921 is an apocalyptic number.

It is an amenable number.

11636905921 is a deficient number, since it is larger than the sum of its proper divisors (437530943).

11636905921 is a wasteful number, since it uses less digits than its factorization.

11636905921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3960.

The product of its (nonzero) digits is 87480, while the sum is 43.

It can be divided in two parts, 1163690 and 5921, that added together give a palindrome (1169611).

The spelling of 11636905921 in words is "eleven billion, six hundred thirty-six million, nine hundred five thousand, nine hundred twenty-one".