11491009920 has 960 divisors, whose sum is σ = 47741324400. Its totient is φ = 2617049088.

The previous prime is 11491009891. The next prime is 11491009951. The reversal of 11491009920 is 2990019411.

It is a tau number, because it is divible by the number of its divisors (960).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 194762851 + ... + 194762909.

Almost surely, 2^11491009920 is an apocalyptic number.

11491009920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 11491009920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23870662200).

11491009920 is an abundant number, since it is smaller than the sum of its proper divisors (36250314480).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

11491009920 is a wasteful number, since it uses less digits than its factorization.

11491009920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137 (or 99 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 36.

The spelling of 11491009920 in words is "eleven billion, four hundred ninety-one million, nine thousand, nine hundred twenty".