121821991199 has 8 divisors (see below), whose sum is σ = 127408174080. Its totient is φ = 116259939576.

The previous prime is 121821991183. The next prime is 121821991271. The reversal of 121821991199 is 991199128121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 121821991199 - 2⁴ = 121821991183 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 121821991199.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121821991169) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6022487 + ... + 6042680.

It is an arithmetic number, because the mean of its divisors is an integer number (15926021760).

Almost surely, 2^121821991199 is an apocalyptic number.

121821991199 is a deficient number, since it is larger than the sum of its proper divisors (5586182881).

121821991199 is a wasteful number, since it uses less digits than its factorization.

121821991199 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12065629.

The product of its digits is 209952, while the sum is 53.

The spelling of 121821991199 in words is "one hundred twenty-one billion, eight hundred twenty-one million, nine hundred ninety-one thousand, one hundred ninety-nine".