231321407 has 2 divisors, whose sum is σ = 231321408. Its totient is φ = 231321406.

The previous prime is 231321383. The next prime is 231321443. The reversal of 231321407 is 704123132.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 231321407 - 2¹⁴ = 231305023 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231321107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115660703 + 115660704.

It is an arithmetic number, because the mean of its divisors is an integer number (115660704).

Almost surely, 2^231321407 is an apocalyptic number.

231321407 is a deficient number, since it is larger than the sum of its proper divisors (1).

231321407 is an equidigital number, since it uses as much as digits as its factorization.

231321407 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1008, while the sum is 23.

The square root of 231321407 is about 15209.2539922246. The cubic root of 231321407 is about 613.8636844729.

Adding to 231321407 its reverse (704123132), we get a palindrome (935444539).

The spelling of 231321407 in words is "two hundred thirty-one million, three hundred twenty-one thousand, four hundred seven".