231404621 has 4 divisors (see below), whose sum is σ = 264462432. Its totient is φ = 198346812.

The previous prime is 231404603. The next prime is 231404651. The reversal of 231404621 is 126404132.

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 a cyclic number.

It is not a de Polignac number, because 231404621 - 2¹⁴ = 231388237 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231404651) 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, 16528895 + ... + 16528908.

It is an arithmetic number, because the mean of its divisors is an integer number (66115608).

Almost surely, 2^231404621 is an apocalyptic number.

It is an amenable number.

231404621 is a deficient number, since it is larger than the sum of its proper divisors (33057811).

231404621 is an equidigital number, since it uses as much as digits as its factorization.

231404621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33057810.

The product of its (nonzero) digits is 1152, while the sum is 23.

The square root of 231404621 is about 15211.9893833778. The cubic root of 231404621 is about 613.9372847062.

Adding to 231404621 its reverse (126404132), we get a palindrome (357808753).

The spelling of 231404621 in words is "two hundred thirty-one million, four hundred four thousand, six hundred twenty-one".