231329988 has 18 divisors (see below), whose sum is σ = 584750894. Its totient is φ = 77109984.

The previous prime is 231329983. The next prime is 231330007. The reversal of 231329988 is 889923132.

231329988 is a `hidden beast` number, since 231 + 329 + 98 + 8 = 666.

It can be written as a sum of positive squares in only one way, i.e., 169833024 + 61496964 = 13032^2 + 7842^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231329983) 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 5 ways as a sum of consecutive naturals, for example, 3212881 + ... + 3212952.

Almost surely, 2^231329988 is an apocalyptic number.

It is an amenable number.

231329988 is an abundant number, since it is smaller than the sum of its proper divisors (353420906).

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

231329988 is a wasteful number, since it uses less digits than its factorization.

231329988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6425843 (or 6425838 counting only the distinct ones).

The product of its digits is 186624, while the sum is 45.

The square root of 231329988 is about 15209.5360875998. The cubic root of 231329988 is about 613.8712749206.

The spelling of 231329988 in words is "two hundred thirty-one million, three hundred twenty-nine thousand, nine hundred eighty-eight".