11981388 has 24 divisors (see below), whose sum is σ = 28148400. Its totient is φ = 3966400.

The previous prime is 11981363. The next prime is 11981393. The reversal of 11981388 is 88318911.

11981388 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 an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1563 + ... + 5138.

It is an arithmetic number, because the mean of its divisors is an integer number (1172850).

Almost surely, 2^11981388 is an apocalyptic number.

It is an amenable number.

11981388 is an abundant number, since it is smaller than the sum of its proper divisors (16167012).

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

11981388 is a wasteful number, since it uses less digits than its factorization.

11981388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6857 (or 6855 counting only the distinct ones).

The product of its digits is 13824, while the sum is 39.

The square root of 11981388 is about 3461.4141618708. The cubic root of 11981388 is about 228.8244238113.

The spelling of 11981388 in words is "eleven million, nine hundred eighty-one thousand, three hundred eighty-eight".