231421133 has 2 divisors, whose sum is σ = 231421134. Its totient is φ = 231421132.

The previous prime is 231421123. The next prime is 231421171. The reversal of 231421133 is 331124132.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 216031204 + 15389929 = 14698^2 + 3923^2 .

It is a cyclic number.

It is not a de Polignac number, because 231421133 - 2⁴ = 231421117 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231421123) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115710566 + 115710567.

It is an arithmetic number, because the mean of its divisors is an integer number (115710567).

Almost surely, 2^231421133 is an apocalyptic number.

It is an amenable number.

231421133 is a deficient number, since it is larger than the sum of its proper divisors (1).

231421133 is an equidigital number, since it uses as much as digits as its factorization.

231421133 is an evil number, because the sum of its binary digits is even.

The product of its digits is 432, while the sum is 20.

The square root of 231421133 is about 15212.5321034994. The cubic root of 231421133 is about 613.9518869662.

Adding to 231421133 its reverse (331124132), we get a palindrome (562545265).

The spelling of 231421133 in words is "two hundred thirty-one million, four hundred twenty-one thousand, one hundred thirty-three".