231442220 has 24 divisors (see below), whose sum is σ = 487846800. Its totient is φ = 92230592.

The previous prime is 231442217. The next prime is 231442223. The reversal of 231442220 is 22244132.

It is an interprime number because it is at equal distance from previous prime (231442217) and next prime (231442223).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 231442192 and 231442201.

It is not an unprimeable number, because it can be changed into a prime (231442223) 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, 16130 + ... + 26889.

It is an arithmetic number, because the mean of its divisors is an integer number (20326950).

Almost surely, 2^231442220 is an apocalyptic number.

231442220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

231442220 is an abundant number, since it is smaller than the sum of its proper divisors (256404580).

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

231442220 is a wasteful number, since it uses less digits than its factorization.

231442220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43297 (or 43295 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 20.

The square root of 231442220 is about 15213.2251675968. The cubic root of 231442220 is about 613.9705340823.

Adding to 231442220 its reverse (22244132), we get a palindrome (253686352).

The spelling of 231442220 in words is "two hundred thirty-one million, four hundred forty-two thousand, two hundred twenty".