2100021999 has 8 divisors (see below), whose sum is σ = 2814538032. Its totient is φ = 1392760320.

The previous prime is 2100021991. The next prime is 2100022007. The reversal of 2100021999 is 9991200012.

It is an interprime number because it is at equal distance from previous prime (2100021991) and next prime (2100022007).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 2100021999 - 2³ = 2100021991 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2100021991) 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, 1812912 + ... + 1814069.

It is an arithmetic number, because the mean of its divisors is an integer number (351817254).

Almost surely, 2^2100021999 is an apocalyptic number.

2100021999 is a deficient number, since it is larger than the sum of its proper divisors (714516033).

2100021999 is a wasteful number, since it uses less digits than its factorization.

2100021999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3627177.

The product of its (nonzero) digits is 2916, while the sum is 33.

The square root of 2100021999 is about 45825.9969776982. The cubic root of 2100021999 is about 1280.5836366324.

The spelling of 2100021999 in words is "two billion, one hundred million, twenty-one thousand, nine hundred ninety-nine".