431242391 has 2 divisors, whose sum is σ = 431242392. Its totient is φ = 431242390.

The previous prime is 431242321. The next prime is 431242403. The reversal of 431242391 is 193242134.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-431242391 is a prime.

It is a Chen prime.

It is equal to p_22910573 and since 431242391 and 22910573 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (431242321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 215621195 + 215621196.

It is an arithmetic number, because the mean of its divisors is an integer number (215621196).

Almost surely, 2^431242391 is an apocalyptic number.

431242391 is a deficient number, since it is larger than the sum of its proper divisors (1).

431242391 is an equidigital number, since it uses as much as digits as its factorization.

431242391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5184, while the sum is 29.

The square root of 431242391 is about 20766.3764532958. The cubic root of 431242391 is about 755.5104604630.

The spelling of 431242391 in words is "four hundred thirty-one million, two hundred forty-two thousand, three hundred ninety-one".