431026991 has 2 divisors, whose sum is σ = 431026992. Its totient is φ = 431026990.

The previous prime is 431026987. The next prime is 431026997. The reversal of 431026991 is 199620134.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 431026991 - 2² = 431026987 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (431026997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 215513495 + 215513496.

It is an arithmetic number, because the mean of its divisors is an integer number (215513496).

Almost surely, 2^431026991 is an apocalyptic number.

431026991 is a deficient number, since it is larger than the sum of its proper divisors (1).

431026991 is an equidigital number, since it uses as much as digits as its factorization.

431026991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11664, while the sum is 35.

The square root of 431026991 is about 20761.1895372110. The cubic root of 431026991 is about 755.3846502774.

The spelling of 431026991 in words is "four hundred thirty-one million, twenty-six thousand, nine hundred ninety-one".