231544421 has 4 divisors (see below), whose sum is σ = 231575232. Its totient is φ = 231513612.

The previous prime is 231544387. The next prime is 231544441. The reversal of 231544421 is 124445132.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-231544421 is a prime.

It is a super-2 number, since 2×231544421² = 107225637792450482, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231544441) 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, 4100 + ... + 21906.

It is an arithmetic number, because the mean of its divisors is an integer number (57893808).

Almost surely, 2^231544421 is an apocalyptic number.

It is an amenable number.

231544421 is a deficient number, since it is larger than the sum of its proper divisors (30811).

231544421 is a wasteful number, since it uses less digits than its factorization.

231544421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30810.

The product of its digits is 3840, while the sum is 26.

The square root of 231544421 is about 15216.5837493177. The cubic root of 231544421 is about 614.0608938110.

Adding to 231544421 its reverse (124445132), we get a palindrome (355989553).

The spelling of 231544421 in words is "two hundred thirty-one million, five hundred forty-four thousand, four hundred twenty-one".