231321240 has 96 divisors (see below), whose sum is σ = 754537680. Its totient is φ = 61460736.

The previous prime is 231321191. The next prime is 231321301. The reversal of 231321240 is 42123132.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 113107 + ... + 115133.

Almost surely, 2^231321240 is an apocalyptic number.

231321240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 231321240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (377268840).

231321240 is an abundant number, since it is smaller than the sum of its proper divisors (523216440).

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

231321240 is a wasteful number, since it uses less digits than its factorization.

231321240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2361 (or 2354 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 231321240 is about 15209.2485021450. The cubic root of 231321240 is about 613.8635367488.

Adding to 231321240 its reverse (42123132), we get a palindrome (273444372).

The spelling of 231321240 in words is "two hundred thirty-one million, three hundred twenty-one thousand, two hundred forty".