11801909911 has 4 divisors (see below), whose sum is σ = 12874810824. Its totient is φ = 10729009000.

The previous prime is 11801909887. The next prime is 11801909923. The reversal of 11801909911 is 11990910811.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 11801909911 - 2⁵ = 11801909879 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11801909941) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 536450440 + ... + 536450461.

It is an arithmetic number, because the mean of its divisors is an integer number (3218702706).

Almost surely, 2^11801909911 is an apocalyptic number.

11801909911 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

11801909911 is a deficient number, since it is larger than the sum of its proper divisors (1072900913).

11801909911 is a wasteful number, since it uses less digits than its factorization.

11801909911 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1072900912.

The product of its (nonzero) digits is 5832, while the sum is 40.

The spelling of 11801909911 in words is "eleven billion, eight hundred one million, nine hundred nine thousand, nine hundred eleven".