231598728 has 24 divisors (see below), whose sum is σ = 627246750. Its totient is φ = 77199552.

The previous prime is 231598721. The next prime is 231598729. The reversal of 231598728 is 827895132.

It is a happy number.

231598728 is a `hidden beast` number, since 2 + 31 + 598 + 7 + 28 = 666.

It can be written as a sum of positive squares in only one way, i.e., 161340804 + 70257924 = 12702^2 + 8382^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is a super-2 number, since 2×231598728² = 107275941622435968, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (231598721) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1608253 + ... + 1608396.

Almost surely, 2^231598728 is an apocalyptic number.

It is an amenable number.

231598728 is an abundant number, since it is smaller than the sum of its proper divisors (395648022).

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

231598728 is a wasteful number, since it uses less digits than its factorization.

231598728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3216661 (or 3216654 counting only the distinct ones).

The product of its digits is 241920, while the sum is 45.

The square root of 231598728 is about 15218.3681122517. The cubic root of 231598728 is about 614.1088978441.

The spelling of 231598728 in words is "two hundred thirty-one million, five hundred ninety-eight thousand, seven hundred twenty-eight".