231220724 has 12 divisors (see below), whose sum is σ = 462441504. Its totient is φ = 99094584.

The previous prime is 231220721. The next prime is 231220727. The reversal of 231220724 is 427022132.

It is a happy number.

231220724 is digitally balanced in base 2, 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 (231220721) and next prime (231220727).

231220724 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 231220724.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231220721) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4128914 + ... + 4128969.

It is an arithmetic number, because the mean of its divisors is an integer number (38536792).

Almost surely, 2^231220724 is an apocalyptic number.

It is an amenable number.

231220724 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

231220724 is a wasteful number, since it uses less digits than its factorization.

231220724 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8257894 (or 8257892 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 23.

The square root of 231220724 is about 15205.9437063275. The cubic root of 231220724 is about 613.7746098425.

Adding to 231220724 its reverse (427022132), we get a palindrome (658242856).

The spelling of 231220724 in words is "two hundred thirty-one million, two hundred twenty thousand, seven hundred twenty-four".