11891332440 has 128 divisors (see below), whose sum is σ = 42686884800. Its totient is φ = 2927093760.

The previous prime is 11891332433. The next prime is 11891332441. The reversal of 11891332440 is 4423319811.

11891332440 is a `hidden beast` number, since 1 + 1 + 89 + 133 + 2 + 440 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 11891332395 and 11891332404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11891332441) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 409441 + ... + 437520.

Almost surely, 2^11891332440 is an apocalyptic number.

11891332440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

11891332440 is an abundant number, since it is smaller than the sum of its proper divisors (30795552360).

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

11891332440 is a wasteful number, since it uses less digits than its factorization.

11891332440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 846994 (or 846984 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The spelling of 11891332440 in words is "eleven billion, eight hundred ninety-one million, three hundred thirty-two thousand, four hundred forty".