1121999999 has 4 divisors (see below), whose sum is σ = 1137369936. Its totient is φ = 1106630064.

The previous prime is 1121999993. The next prime is 1122000013. The reversal of 1121999999 is 9999991211.

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 1121999999 - 2⁸ = 1121999743 is a prime.

It is a Duffinian number.

1121999999 is a modest number, since divided by 99999 gives 11219 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1121999993) 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, 7684859 + ... + 7685004.

It is an arithmetic number, because the mean of its divisors is an integer number (284342484).

Almost surely, 2^1121999999 is an apocalyptic number.

1121999999 is a deficient number, since it is larger than the sum of its proper divisors (15369937).

1121999999 is an equidigital number, since it uses as much as digits as its factorization.

1121999999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15369936.

The product of its digits is 1062882, while the sum is 59.

The square root of 1121999999 is about 33496.2684339614. The cubic root of 1121999999 is about 1039.1166065370.

The spelling of 1121999999 in words is "one billion, one hundred twenty-one million, nine hundred ninety-nine thousand, nine hundred ninety-nine".