11981809604 has 48 divisors (see below), whose sum is σ = 21851155200. Its totient is φ = 5743685376.

The previous prime is 11981809601. The next prime is 11981809607. The reversal of 11981809604 is 40690818911.

It is an interprime number because it is at equal distance from previous prime (11981809601) and next prime (11981809607).

It is a super-2 number, since 2×11981809604² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (11981809601) 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, 10042832 + ... + 10044024.

It is an arithmetic number, because the mean of its divisors is an integer number (455232400).

Almost surely, 2^11981809604 is an apocalyptic number.

It is an amenable number.

11981809604 is a deficient number, since it is larger than the sum of its proper divisors (9869345596).

11981809604 is a wasteful number, since it uses less digits than its factorization.

11981809604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2172 (or 2170 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 47.

The spelling of 11981809604 in words is "eleven billion, nine hundred eighty-one million, eight hundred nine thousand, six hundred four".