999129823 has 2 divisors, whose sum is σ = 999129824. Its totient is φ = 999129822.

The previous prime is 999129809. The next prime is 999129829. The reversal of 999129823 is 328921999.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-999129823 is a prime.

It is a super-2 number, since 2×999129823² = 1996520806416022658, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999129829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499564911 + 499564912.

It is an arithmetic number, because the mean of its divisors is an integer number (499564912).

Almost surely, 2^999129823 is an apocalyptic number.

999129823 is a deficient number, since it is larger than the sum of its proper divisors (1).

999129823 is an equidigital number, since it uses as much as digits as its factorization.

999129823 is an evil number, because the sum of its binary digits is even.

The product of its digits is 629856, while the sum is 52.

The square root of 999129823 is about 31609.0149008159. The cubic root of 999129823 is about 999.7098568251.

The spelling of 999129823 in words is "nine hundred ninety-nine million, one hundred twenty-nine thousand, eight hundred twenty-three".