1999991118 has 16 divisors (see below), whose sum is σ = 4108090320. Its totient is φ = 648645696.

The previous prime is 1999991113. The next prime is 1999991131. The reversal of 1999991118 is 8111999991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1999991113) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4504263 + ... + 4504706.

It is an arithmetic number, because the mean of its divisors is an integer number (256755645).

Almost surely, 2^1999991118 is an apocalyptic number.

1999991118 is an abundant number, since it is smaller than the sum of its proper divisors (2108099202).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1999991118 is a wasteful number, since it uses less digits than its factorization.

1999991118 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9009011.

The product of its digits is 472392, while the sum is 57.

The square root of 1999991118 is about 44721.2602461067. The cubic root of 1999991118 is about 1259.9191847890.

The spelling of 1999991118 in words is "one billion, nine hundred ninety-nine million, nine hundred ninety-one thousand, one hundred eighteen".