111781475988 has 144 divisors (see below), whose sum is σ = 329366620800. Its totient is φ = 29480645376.

The previous prime is 111781475947. The next prime is 111781476017. The reversal of 111781475988 is 889574187111.

It is a super-2 number, since 2×111781475988² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 615256 + ... + 775952.

It is an arithmetic number, because the mean of its divisors is an integer number (2287268200).

Almost surely, 2^111781475988 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 111781475988, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (164683310400).

111781475988 is an abundant number, since it is smaller than the sum of its proper divisors (217585144812).

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

111781475988 is a wasteful number, since it uses less digits than its factorization.

111781475988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160751 (or 160722 counting only the distinct ones).

The product of its digits is 4515840, while the sum is 60.

The spelling of 111781475988 in words is "one hundred eleven billion, seven hundred eighty-one million, four hundred seventy-five thousand, nine hundred eighty-eight".