231205155 has 16 divisors (see below), whose sum is σ = 371053824. Its totient is φ = 122934240.

The previous prime is 231205153. The next prime is 231205159. The reversal of 231205155 is 551502132.

It is a happy number.

It is not a de Polignac number, because 231205155 - 2¹ = 231205153 is a prime.

It is not an unprimeable number, because it can be changed into a prime (231205153) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18319 + ... + 28248.

It is an arithmetic number, because the mean of its divisors is an integer number (23190864).

Almost surely, 2^231205155 is an apocalyptic number.

231205155 is a deficient number, since it is larger than the sum of its proper divisors (139848669).

231205155 is a wasteful number, since it uses less digits than its factorization.

231205155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46906.

The product of its (nonzero) digits is 1500, while the sum is 24.

The square root of 231205155 is about 15205.4317597364. The cubic root of 231205155 is about 613.7608335811.

Adding to 231205155 its reverse (551502132), we get a palindrome (782707287).

The spelling of 231205155 in words is "two hundred thirty-one million, two hundred five thousand, one hundred fifty-five".