143871991 has 2 divisors, whose sum is σ = 143871992. Its totient is φ = 143871990.

The previous prime is 143871989. The next prime is 143871997. The reversal of 143871991 is 199178341.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 143871991 - 2¹ = 143871989 is a prime.

Together with 143871989, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (143871997) 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, 71935995 + 71935996.

It is an arithmetic number, because the mean of its divisors is an integer number (71935996).

Almost surely, 2^143871991 is an apocalyptic number.

143871991 is a deficient number, since it is larger than the sum of its proper divisors (1).

143871991 is an equidigital number, since it uses as much as digits as its factorization.

143871991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 54432, while the sum is 43.

The square root of 143871991 is about 11994.6651057877. The cubic root of 143871991 is about 523.9929186833.

The spelling of 143871991 in words is "one hundred forty-three million, eight hundred seventy-one thousand, nine hundred ninety-one".