20121200109999 has 6 divisors (see below), whose sum is σ = 29063955714456. Its totient is φ = 13414133406660.

The previous prime is 20121200109977. The next prime is 20121200110003. The reversal of 20121200109999 is 99990100212102.

It is not a de Polignac number, because 20121200109999 - 2¹⁷ = 20121199978927 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20121200109499) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1117844450547 + ... + 1117844450564.

It is an arithmetic number, because the mean of its divisors is an integer number (4843992619076).

Almost surely, 2^{20121200109999} is an apocalyptic number.

20121200109999 is a deficient number, since it is larger than the sum of its proper divisors (8942755604457).

20121200109999 is a wasteful number, since it uses less digits than its factorization.

20121200109999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2235688901117 (or 2235688901114 counting only the distinct ones).

The product of its (nonzero) digits is 52488, while the sum is 45.

The spelling of 20121200109999 in words is "twenty trillion, one hundred twenty-one billion, two hundred million, one hundred nine thousand, nine hundred ninety-nine".