231133440 has 144 divisors (see below), whose sum is σ = 770571648. Its totient is φ = 58933248.

The previous prime is 231133429. The next prime is 231133447. The reversal of 231133440 is 44331132.

231133440 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (231133447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 87012 + ... + 89628.

It is an arithmetic number, because the mean of its divisors is an integer number (5351192).

Almost surely, 2^231133440 is an apocalyptic number.

231133440 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 231133440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (385285824).

231133440 is an abundant number, since it is smaller than the sum of its proper divisors (539438208).

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

231133440 is a wasteful number, since it uses less digits than its factorization.

231133440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2664 (or 2650 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 21.

The square root of 231133440 is about 15203.0733734992. The cubic root of 231133440 is about 613.6973684306.

Adding to 231133440 its reverse (44331132), we get a palindrome (275464572).

The spelling of 231133440 in words is "two hundred thirty-one million, one hundred thirty-three thousand, four hundred forty".