991424023 has 8 divisors (see below), whose sum is σ = 1022043600. Its totient is φ = 961265088.

The previous prime is 991423967. The next prime is 991424029. The reversal of 991424023 is 320424199.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-991424023 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 991424023.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991424029) 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 in 7 ways as a sum of consecutive naturals, for example, 110788 + ... + 119401.

It is an arithmetic number, because the mean of its divisors is an integer number (127755450).

Almost surely, 2^991424023 is an apocalyptic number.

991424023 is a deficient number, since it is larger than the sum of its proper divisors (30619577).

991424023 is a wasteful number, since it uses less digits than its factorization.

991424023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 230321.

The product of its (nonzero) digits is 15552, while the sum is 34.

The square root of 991424023 is about 31486.8865243930. The cubic root of 991424023 is about 997.1331299101.

The spelling of 991424023 in words is "nine hundred ninety-one million, four hundred twenty-four thousand, twenty-three".