991502143 has 2 divisors, whose sum is σ = 991502144. Its totient is φ = 991502142.

The previous prime is 991502131. The next prime is 991502207. The reversal of 991502143 is 341205199.

It is a weak prime.

It is an emirp because it is prime and its reverse (341205199) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-991502143 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 991502099 and 991502108.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (991502123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495751071 + 495751072.

It is an arithmetic number, because the mean of its divisors is an integer number (495751072).

Almost surely, 2^991502143 is an apocalyptic number.

991502143 is a deficient number, since it is larger than the sum of its proper divisors (1).

991502143 is an equidigital number, since it uses as much as digits as its factorization.

991502143 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9720, while the sum is 34.

The square root of 991502143 is about 31488.1270163851. The cubic root of 991502143 is about 997.1593191734.

The spelling of 991502143 in words is "nine hundred ninety-one million, five hundred two thousand, one hundred forty-three".