11981420 has 36 divisors (see below), whose sum is σ = 27661872. Its totient is φ = 4356000.

The previous prime is 11981399. The next prime is 11981423. The reversal of 11981420 is 2418911.

It is a self number, because there is not a number n which added to its sum of digits gives 11981420.

It is not an unprimeable number, because it can be changed into a prime (11981423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 56 + ... + 4895.

Almost surely, 2^11981420 is an apocalyptic number.

11981420 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 11981420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13830936).

11981420 is an abundant number, since it is smaller than the sum of its proper divisors (15680452).

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

11981420 is a wasteful number, since it uses less digits than its factorization.

11981420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4982 (or 4969 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 26.

The square root of 11981420 is about 3461.4187842560. The cubic root of 11981420 is about 228.8246275266.

The spelling of 11981420 in words is "eleven million, nine hundred eighty-one thousand, four hundred twenty".