11909490921 has 36 divisors (see below), whose sum is σ = 17755146864. Its totient is φ = 7692300000.

The previous prime is 11909490911. The next prime is 11909491003. The reversal of 11909490921 is 12909490911.

It is not a de Polignac number, because 11909490921 - 2⁷ = 11909490793 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11909490911) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 3090646 + ... + 3094496.

It is an arithmetic number, because the mean of its divisors is an integer number (493198524).

Almost surely, 2^11909490921 is an apocalyptic number.

It is an amenable number.

11909490921 is a deficient number, since it is larger than the sum of its proper divisors (5845655943).

11909490921 is a wasteful number, since it uses less digits than its factorization.

11909490921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4182 (or 4142 counting only the distinct ones).

The product of its (nonzero) digits is 52488, while the sum is 45.

The spelling of 11909490921 in words is "eleven billion, nine hundred nine million, four hundred ninety thousand, nine hundred twenty-one".