231214721 has 2 divisors, whose sum is σ = 231214722. Its totient is φ = 231214720.

The previous prime is 231214681. The next prime is 231214723. The reversal of 231214721 is 127412132.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 226201600 + 5013121 = 15040^2 + 2239^2 .

It is a cyclic number.

It is not a de Polignac number, because 231214721 - 2¹⁴ = 231198337 is a prime.

Together with 231214723, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (231214723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115607360 + 115607361.

It is an arithmetic number, because the mean of its divisors is an integer number (115607361).

Almost surely, 2^231214721 is an apocalyptic number.

It is an amenable number.

231214721 is a deficient number, since it is larger than the sum of its proper divisors (1).

231214721 is an equidigital number, since it uses as much as digits as its factorization.

231214721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 672, while the sum is 23.

The square root of 231214721 is about 15205.7463151271. The cubic root of 231214721 is about 613.7692981489.

Adding to 231214721 its reverse (127412132), we get a palindrome (358626853).

The spelling of 231214721 in words is "two hundred thirty-one million, two hundred fourteen thousand, seven hundred twenty-one".