231140220 has 24 divisors (see below), whose sum is σ = 647192784. Its totient is φ = 61637376.

The previous prime is 231140207. The next prime is 231140227. The reversal of 231140220 is 22041132.

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

It is a self number, because there is not a number n which added to its sum of digits gives 231140220.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231140227) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1926109 + ... + 1926228.

It is an arithmetic number, because the mean of its divisors is an integer number (26966366).

Almost surely, 2^231140220 is an apocalyptic number.

231140220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

231140220 is an abundant number, since it is smaller than the sum of its proper divisors (416052564).

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

231140220 is a wasteful number, since it uses less digits than its factorization.

231140220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3852349 (or 3852347 counting only the distinct ones).

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

The square root of 231140220 is about 15203.2963530940. The cubic root of 231140220 is about 613.7033690443.

Adding to 231140220 its reverse (22041132), we get a palindrome (253181352).

The spelling of 231140220 in words is "two hundred thirty-one million, one hundred forty thousand, two hundred twenty".