231657428 has 6 divisors (see below), whose sum is σ = 405400506. Its totient is φ = 115828712.

The previous prime is 231657427. The next prime is 231657457. The reversal of 231657428 is 824756132.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 224160784 + 7496644 = 14972^2 + 2738^2 .

It is a junction number, because it is equal to n+sod(n) for n = 231657391 and 231657400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231657427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28957175 + ... + 28957182.

It is an arithmetic number, because the mean of its divisors is an integer number (67566751).

Almost surely, 2^231657428 is an apocalyptic number.

It is an amenable number.

231657428 is a deficient number, since it is larger than the sum of its proper divisors (173743078).

231657428 is a wasteful number, since it uses less digits than its factorization.

231657428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57914361 (or 57914359 counting only the distinct ones).

The product of its digits is 80640, while the sum is 38.

The square root of 231657428 is about 15220.2965805532. The cubic root of 231657428 is about 614.1607765792.

The spelling of 231657428 in words is "two hundred thirty-one million, six hundred fifty-seven thousand, four hundred twenty-eight".