2121221211999 has 16 divisors (see below), whose sum is σ = 2917531579008. Its totient is φ = 1369865902752.

The previous prime is 2121221211983. The next prime is 2121221212009. The reversal of 2121221211999 is 9991121221212.

It is not a de Polignac number, because 2121221211999 - 2⁴ = 2121221211983 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2121221211999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121221211919) 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, 42067537 + ... + 42117930.

It is an arithmetic number, because the mean of its divisors is an integer number (182345723688).

Almost surely, 2^{2121221211999} is an apocalyptic number.

2121221211999 is a deficient number, since it is larger than the sum of its proper divisors (796310367009).

2121221211999 is a wasteful number, since it uses less digits than its factorization.

2121221211999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84185734.

The product of its digits is 23328, while the sum is 42.

The spelling of 2121221211999 in words is "two trillion, one hundred twenty-one billion, two hundred twenty-one million, two hundred eleven thousand, nine hundred ninety-nine".