999161999 has 4 divisors (see below), whose sum is σ = 1089994920. Its totient is φ = 908329080.

The previous prime is 999161963. The next prime is 999162001.

999161999 is nontrivially palindromic in base 10.

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 999161999 - 2²⁰ = 998113423 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999161939) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45416444 + ... + 45416465.

It is an arithmetic number, because the mean of its divisors is an integer number (272498730).

Almost surely, 2^999161999 is an apocalyptic number.

999161999 is a deficient number, since it is larger than the sum of its proper divisors (90832921).

999161999 is a wasteful number, since it uses less digits than its factorization.

999161999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90832920.

The product of its digits is 3188646, while the sum is 62.

The square root of 999161999 is about 31609.5238654428. The cubic root of 999161999 is about 999.7205882697.

The spelling of 999161999 in words is "nine hundred ninety-nine million, one hundred sixty-one thousand, nine hundred ninety-nine".