11971920 has 80 divisors (see below), whose sum is σ = 37622592. Its totient is φ = 3148800.

The previous prime is 11971913. The next prime is 11971943. The reversal of 11971920 is 2917911.

11971920 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19620 + ... + 20220.

Almost surely, 2^11971920 is an apocalyptic number.

11971920 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 11971920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18811296).

11971920 is an abundant number, since it is smaller than the sum of its proper divisors (25650672).

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

11971920 is a wasteful number, since it uses less digits than its factorization.

11971920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 700 (or 694 counting only the distinct ones).

The product of its (nonzero) digits is 1134, while the sum is 30.

The square root of 11971920 is about 3460.0462424656. The cubic root of 11971920 is about 228.7641336186.

The spelling of 11971920 in words is "eleven million, nine hundred seventy-one thousand, nine hundred twenty".