331881138 has 48 divisors (see below), whose sum is σ = 763098336. Its totient is φ = 108047520.

The previous prime is 331881131. The next prime is 331881149. The reversal of 331881138 is 831188133.

It is a super-2 number, since 2×331881138² = 220290179520350088, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (331881131) 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 23 ways as a sum of consecutive naturals, for example, 12958 + ... + 28838.

It is an arithmetic number, because the mean of its divisors is an integer number (15897882).

Almost surely, 2^331881138 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 331881138, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (381549168).

331881138 is an abundant number, since it is smaller than the sum of its proper divisors (431217198).

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

331881138 is a wasteful number, since it uses less digits than its factorization.

331881138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15941 (or 15929 counting only the distinct ones).

The product of its digits is 13824, while the sum is 36.

The square root of 331881138 is about 18217.6051664317. The cubic root of 331881138 is about 692.3529125847.

The spelling of 331881138 in words is "three hundred thirty-one million, eight hundred eighty-one thousand, one hundred thirty-eight".