231021240 has 32 divisors (see below), whose sum is σ = 693064080. Its totient is φ = 61605632.

The previous prime is 231021233. The next prime is 231021257. The reversal of 231021240 is 42120132.

231021240 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×231021240² = 106741626662275200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 962469 + ... + 962708.

Almost surely, 2^231021240 is an apocalyptic number.

231021240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

231021240 is an abundant number, since it is smaller than the sum of its proper divisors (462042840).

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

231021240 is a wasteful number, since it uses less digits than its factorization.

231021240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1925191 (or 1925187 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 231021240 is about 15199.3828822094. The cubic root of 231021240 is about 613.5980491952.

Adding to 231021240 its reverse (42120132), we get a palindrome (273141372).

It can be divided in two parts, 23102 and 1240, that added together give a palindrome (24342).

The spelling of 231021240 in words is "two hundred thirty-one million, twenty-one thousand, two hundred forty".