231331413 has 4 divisors (see below), whose sum is σ = 308441888. Its totient is φ = 154220940.

The previous prime is 231331409. The next prime is 231331421. The reversal of 231331413 is 314133132.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 231331413 - 2² = 231331409 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 231331413.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231331423) 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, 38555233 + ... + 38555238.

It is an arithmetic number, because the mean of its divisors is an integer number (77110472).

Almost surely, 2^231331413 is an apocalyptic number.

It is an amenable number.

231331413 is a deficient number, since it is larger than the sum of its proper divisors (77110475).

231331413 is an equidigital number, since it uses as much as digits as its factorization.

231331413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77110474.

The product of its digits is 648, while the sum is 21.

The square root of 231331413 is about 15209.5829331379. The cubic root of 231331413 is about 613.8725354068.

Adding to 231331413 its reverse (314133132), we get a palindrome (545464545).

The spelling of 231331413 in words is "two hundred thirty-one million, three hundred thirty-one thousand, four hundred thirteen".