231220736 has 40 divisors (see below), whose sum is σ = 467641944. Its totient is φ = 114196480.

The previous prime is 231220727. The next prime is 231220739. The reversal of 231220736 is 637022132.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231220739) 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, 39776 + ... + 45216.

Almost surely, 2^231220736 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 231220736, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (233820972).

231220736 is an abundant number, since it is smaller than the sum of its proper divisors (236421208).

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

231220736 is an frugal number, since it uses more digits than its factorization.

231220736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5542 (or 5526 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 26.

The square root of 231220736 is about 15205.9441009100. The cubic root of 231220736 is about 613.7746204605.

Adding to 231220736 its reverse (637022132), we get a palindrome (868242868).

The spelling of 231220736 in words is "two hundred thirty-one million, two hundred twenty thousand, seven hundred thirty-six".