2121020021999 has 16 divisors (see below), whose sum is σ = 2260461173760. Its totient is φ = 1983219189120.

The previous prime is 2121020021987. The next prime is 2121020022001. The reversal of 2121020021999 is 9991200201212.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2121020021999 is a prime.

It is a super-3 number, since 3×2121020021999³ (a number of 38 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121020021969) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6884834 + ... + 7186304.

It is an arithmetic number, because the mean of its divisors is an integer number (141278823360).

Almost surely, 2^{2121020021999} is an apocalyptic number.

2121020021999 is a deficient number, since it is larger than the sum of its proper divisors (139441151761).

2121020021999 is a wasteful number, since it uses less digits than its factorization.

2121020021999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 304190.

The product of its (nonzero) digits is 11664, while the sum is 38.

The spelling of 2121020021999 in words is "two trillion, one hundred twenty-one billion, twenty million, twenty-one thousand, nine hundred ninety-nine".