121099999999 has 4 divisors (see below), whose sum is σ = 132109090920. Its totient is φ = 110090909080.

The previous prime is 121099999981. The next prime is 121100000051. The reversal of 121099999999 is 999999990121.

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

It is a cyclic number.

It is not a de Polignac number, because 121099999999 - 2³⁵ = 86740261631 is a prime.

It is a Duffinian number.

121099999999 is a modest number, since divided by 999999 gives 121099 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121099999199) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5504545444 + ... + 5504545465.

It is an arithmetic number, because the mean of its divisors is an integer number (33027272730).

Almost surely, 2^121099999999 is an apocalyptic number.

121099999999 is a deficient number, since it is larger than the sum of its proper divisors (11009090921).

121099999999 is a wasteful number, since it uses less digits than its factorization.

121099999999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11009090920.

The product of its (nonzero) digits is 86093442, while the sum is 76.

It can be divided in two parts, 12 and 1099999999, that added together give a palindrome (1100000011).

The spelling of 121099999999 in words is "one hundred twenty-one billion, ninety-nine million, nine hundred ninety-nine thousand, nine hundred ninety-nine".