999502991 has 16 divisors (see below), whose sum is σ = 1032151680. Its totient is φ = 967468320.

The previous prime is 999502963. The next prime is 999503003. The reversal of 999502991 is 199205999.

It is a cyclic number.

It is not a de Polignac number, because 999502991 - 2¹⁰ = 999501967 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (53).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999502921) 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 15 ways as a sum of consecutive naturals, for example, 1554116 + ... + 1554758.

It is an arithmetic number, because the mean of its divisors is an integer number (64509480).

Almost surely, 2^999502991 is an apocalyptic number.

999502991 is a deficient number, since it is larger than the sum of its proper divisors (32648689).

999502991 is a wasteful number, since it uses less digits than its factorization.

999502991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1046.

The product of its (nonzero) digits is 590490, while the sum is 53.

The square root of 999502991 is about 31614.9172227289. The cubic root of 999502991 is about 999.8343028793.

The spelling of 999502991 in words is "nine hundred ninety-nine million, five hundred two thousand, nine hundred ninety-one".