231203121 has 16 divisors (see below), whose sum is σ = 317376000. Its totient is φ = 149603328.

The previous prime is 231203117. The next prime is 231203129. The reversal of 231203121 is 121302132.

It is not a de Polignac number, because 231203121 - 2² = 231203117 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 231203121.

It is not an unprimeable number, because it can be changed into a prime (231203129) 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, 47520 + ... + 52158.

It is an arithmetic number, because the mean of its divisors is an integer number (19836000).

Almost surely, 2^231203121 is an apocalyptic number.

It is an amenable number.

231203121 is a deficient number, since it is larger than the sum of its proper divisors (86172879).

231203121 is a wasteful number, since it uses less digits than its factorization.

231203121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5128.

The product of its (nonzero) digits is 72, while the sum is 15.

The square root of 231203121 is about 15205.3648755957. The cubic root of 231203121 is about 613.7590337464.

Adding to 231203121 its reverse (121302132), we get a palindrome (352505253).

The spelling of 231203121 in words is "two hundred thirty-one million, two hundred three thousand, one hundred twenty-one".