143431991 has 2 divisors, whose sum is σ = 143431992. Its totient is φ = 143431990.

The previous prime is 143431987. The next prime is 143432021. The reversal of 143431991 is 199134341.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 143431991 - 2² = 143431987 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 (143431591) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 71715995 + 71715996.

It is an arithmetic number, because the mean of its divisors is an integer number (71715996).

Almost surely, 2^143431991 is an apocalyptic number.

143431991 is a deficient number, since it is larger than the sum of its proper divisors (1).

143431991 is an equidigital number, since it uses as much as digits as its factorization.

143431991 is an odious number, because the sum of its binary digits is odd.

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

The square root of 143431991 is about 11976.3095734872. The cubic root of 143431991 is about 523.4582018651.

The spelling of 143431991 in words is "one hundred forty-three million, four hundred thirty-one thousand, nine hundred ninety-one".