231643620 has 72 divisors (see below), whose sum is σ = 756710136. Its totient is φ = 57019392.

The previous prime is 231643613. The next prime is 231643627. The reversal of 231643620 is 26346132.

231643620 is a `hidden beast` number, since 2 + 31 + 6 + 4 + 3 + 620 = 666.

231643620 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (231643613) and next prime (231643627).

It can be written as a sum of positive squares in 4 ways, for example, as 38044224 + 193599396 = 6168^2 + 13914^2 .

It is not an unprimeable number, because it can be changed into a prime (231643627) 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, 47157 + ... + 51836.

It is an arithmetic number, because the mean of its divisors is an integer number (10509863).

Almost surely, 2^231643620 is an apocalyptic number.

231643620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

231643620 is an abundant number, since it is smaller than the sum of its proper divisors (525066516).

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

231643620 is a wasteful number, since it uses less digits than its factorization.

231643620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99021 (or 99016 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 27.

The square root of 231643620 is about 15219.8429689665. The cubic root of 231643620 is about 614.1485739336.

Adding to 231643620 its reverse (26346132), we get a palindrome (257989752).

The spelling of 231643620 in words is "two hundred thirty-one million, six hundred forty-three thousand, six hundred twenty".