11961920 has 56 divisors (see below), whose sum is σ = 29489400. Its totient is φ = 4616192.

The previous prime is 11961899. The next prime is 11961967. The reversal of 11961920 is 2916911.

It can be written as a sum of positive squares in 4 ways, for example, as 2768896 + 9193024 = 1664^2 + 3032^2 .

It is a Harshad number since it is a multiple of its sum of digits (29).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8636 + ... + 9924.

Almost surely, 2^11961920 is an apocalyptic number.

11961920 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 11961920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14744700).

11961920 is an abundant number, since it is smaller than the sum of its proper divisors (17527480).

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

11961920 is a wasteful number, since it uses less digits than its factorization.

11961920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1335 (or 1325 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 29.

The square root of 11961920 is about 3458.6008731856. The cubic root of 11961920 is about 228.7004212378.

The spelling of 11961920 in words is "eleven million, nine hundred sixty-one thousand, nine hundred twenty".