2001221200999 has 2 divisors, whose sum is σ = 2001221201000. Its totient is φ = 2001221200998.

The previous prime is 2001221200967. The next prime is 2001221201017. The reversal of 2001221200999 is 9990021221002.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2001221200999 - 2⁵ = 2001221200967 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2001221204999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1000610600499 + 1000610600500.

It is an arithmetic number, because the mean of its divisors is an integer number (1000610600500).

Almost surely, 2^{2001221200999} is an apocalyptic number.

2001221200999 is a deficient number, since it is larger than the sum of its proper divisors (1).

2001221200999 is an equidigital number, since it uses as much as digits as its factorization.

2001221200999 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11664, while the sum is 37.

The spelling of 2001221200999 in words is "two trillion, one billion, two hundred twenty-one million, two hundred thousand, nine hundred ninety-nine".