121200021000019 has 4 divisors (see below), whose sum is σ = 130523099538496. Its totient is φ = 111876942461544.

The previous prime is 121200020999899. The next prime is 121200021000031. The reversal of 121200021000019 is 910000120002121.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 121200021000019 - 2¹⁵ = 121200020967251 is a prime.

It is a super-2 number, since 2×121200021000019² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121200021000049) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4661539269219 + ... + 4661539269244.

It is an arithmetic number, because the mean of its divisors is an integer number (32630774884624).

Almost surely, 2^{121200021000019} is an apocalyptic number.

121200021000019 is a deficient number, since it is larger than the sum of its proper divisors (9323078538477).

121200021000019 is an equidigital number, since it uses as much as digits as its factorization.

121200021000019 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9323078538476.

The product of its (nonzero) digits is 72, while the sum is 19.

The spelling of 121200021000019 in words is "one hundred twenty-one trillion, two hundred billion, twenty-one million, nineteen", and thus it is an aban number.