11891920 has 60 divisors (see below), whose sum is σ = 29005956. Its totient is φ = 4533760.

The previous prime is 11891917. The next prime is 11891933. The reversal of 11891920 is 2919811.

11891920 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 6170256 + 5721664 = 2484^2 + 2392^2 .

It is a super-2 number, since 2×11891920² = 282835522572800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 42180 + ... + 42460.

Almost surely, 2^11891920 is an apocalyptic number.

11891920 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 11891920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14502978).

11891920 is an abundant number, since it is smaller than the sum of its proper divisors (17114036).

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

11891920 is a wasteful number, since it uses less digits than its factorization.

11891920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 340 (or 311 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 31.

The square root of 11891920 is about 3448.4663257744. The cubic root of 11891920 is about 228.2534372762.

The spelling of 11891920 in words is "eleven million, eight hundred ninety-one thousand, nine hundred twenty".