231542405 has 4 divisors (see below), whose sum is σ = 277850892. Its totient is φ = 185233920.

The previous prime is 231542387. The next prime is 231542413. The reversal of 231542405 is 504245132.

It is a happy number.

231542405 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 149059681 + 82482724 = 12209^2 + 9082^2 .

It is not a de Polignac number, because 231542405 - 2⁸ = 231542149 is a prime.

It is a super-2 number, since 2×231542405² = 107223770626368050, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23154236 + ... + 23154245.

It is an arithmetic number, because the mean of its divisors is an integer number (69462723).

Almost surely, 2^231542405 is an apocalyptic number.

It is an amenable number.

231542405 is a deficient number, since it is larger than the sum of its proper divisors (46308487).

231542405 is an equidigital number, since it uses as much as digits as its factorization.

231542405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46308486.

The product of its (nonzero) digits is 4800, while the sum is 26.

The square root of 231542405 is about 15216.5175056581. The cubic root of 231542405 is about 614.0591116471.

Adding to 231542405 its reverse (504245132), we get a palindrome (735787537).

The spelling of 231542405 in words is "two hundred thirty-one million, five hundred forty-two thousand, four hundred five".