231618225 has 24 divisors (see below), whose sum is σ = 392287392. Its totient is φ = 120515200.

The previous prime is 231618221. The next prime is 231618229. The reversal of 231618225 is 522816132.

It is an interprime number because it is at equal distance from previous prime (231618221) and next prime (231618229).

It is not a de Polignac number, because 231618225 - 2² = 231618221 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 231618192 and 231618201.

It is not an unprimeable number, because it can be changed into a prime (231618221) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 34587 + ... + 40736.

It is an arithmetic number, because the mean of its divisors is an integer number (16345308).

Almost surely, 2^231618225 is an apocalyptic number.

231618225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

231618225 is a deficient number, since it is larger than the sum of its proper divisors (160669167).

231618225 is a wasteful number, since it uses less digits than its factorization.

231618225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75377 (or 75372 counting only the distinct ones).

The product of its digits is 5760, while the sum is 30.

The square root of 231618225 is about 15219.0086733663. The cubic root of 231618225 is about 614.1261301570.

The spelling of 231618225 in words is "two hundred thirty-one million, six hundred eighteen thousand, two hundred twenty-five".