2121111999 has 48 divisors (see below), whose sum is σ = 3192134400. Its totient is φ = 1356295680.

The previous prime is 2121111989. The next prime is 2121112013. The reversal of 2121111999 is 9991111212.

It is not a de Polignac number, because 2121111999 - 2⁴ = 2121111983 is a prime.

It is a super-2 number, since 2×2121111999² = 8998232224603552002, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121111959) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 9511602 + ... + 9511824.

It is an arithmetic number, because the mean of its divisors is an integer number (66502800).

Almost surely, 2^2121111999 is an apocalyptic number.

2121111999 is a deficient number, since it is larger than the sum of its proper divisors (1071022401).

2121111999 is a wasteful number, since it uses less digits than its factorization.

2121111999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 592 (or 589 counting only the distinct ones).

The product of its digits is 2916, while the sum is 36.

The square root of 2121111999 is about 46055.5316873011. The cubic root of 2121111999 is about 1284.8562268048.

The spelling of 2121111999 in words is "two billion, one hundred twenty-one million, one hundred eleven thousand, nine hundred ninety-nine".