991344143 has 4 divisors (see below), whose sum is σ = 997909488. Its totient is φ = 984778800.

The previous prime is 991344139. The next prime is 991344173. The reversal of 991344143 is 341443199.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 991344143 - 2² = 991344139 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 991344097 and 991344106.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991344173) 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 in 3 ways as a sum of consecutive naturals, for example, 3282446 + ... + 3282747.

It is an arithmetic number, because the mean of its divisors is an integer number (249477372).

Almost surely, 2^991344143 is an apocalyptic number.

991344143 is a deficient number, since it is larger than the sum of its proper divisors (6565345).

991344143 is a wasteful number, since it uses less digits than its factorization.

991344143 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6565344.

The product of its digits is 46656, while the sum is 38.

The square root of 991344143 is about 31485.6180342708. The cubic root of 991344143 is about 997.1063491947.

The spelling of 991344143 in words is "nine hundred ninety-one million, three hundred forty-four thousand, one hundred forty-three".