11981280 has 96 divisors (see below), whose sum is σ = 38253600. Its totient is φ = 3151872.

The previous prime is 11981273. The next prime is 11981297. The reversal of 11981280 is 8218911.

11981280 is digitally balanced in base 2 and base 4, because in such bases 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 (96).

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, 52206 + ... + 52434.

It is an arithmetic number, because the mean of its divisors is an integer number (398475).

Almost surely, 2^11981280 is an apocalyptic number.

11981280 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 11981280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19126800).

11981280 is an abundant number, since it is smaller than the sum of its proper divisors (26272320).

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

11981280 is a wasteful number, since it uses less digits than its factorization.

11981280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 356 (or 348 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 30.

The square root of 11981280 is about 3461.3985612755. The cubic root of 11981280 is about 228.8237362696.

The spelling of 11981280 in words is "eleven million, nine hundred eighty-one thousand, two hundred eighty".