1011999999 has 4 divisors (see below), whose sum is σ = 1349333336. Its totient is φ = 674666664.

The previous prime is 1011999971. The next prime is 1012000009. The reversal of 1011999999 is 9999991101.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 1011999999 - 2⁹ = 1011999487 is a prime.

It is a Duffinian number.

1011999999 is a modest number, since divided by 99999 gives 10119 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1011999799) 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 3 ways as a sum of consecutive naturals, for example, 168666664 + ... + 168666669.

It is an arithmetic number, because the mean of its divisors is an integer number (337333334).

Almost surely, 2^1011999999 is an apocalyptic number.

1011999999 is a deficient number, since it is larger than the sum of its proper divisors (337333337).

1011999999 is an equidigital number, since it uses as much as digits as its factorization.

1011999999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 337333336.

The product of its (nonzero) digits is 531441, while the sum is 57.

The square root of 1011999999 is about 31811.9474254564. The cubic root of 1011999999 is about 1003.9841054901.

The spelling of 1011999999 in words is "one billion, eleven million, nine hundred ninety-nine thousand, nine hundred ninety-nine".