121078905923 has 4 divisors (see below), whose sum is σ = 125254040640. Its totient is φ = 116903771208.

The previous prime is 121078905919. The next prime is 121078905967. The reversal of 121078905923 is 329509870121.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 329509870121 = 67 ⋅4918057763.

It is a cyclic number.

It is not a de Polignac number, because 121078905923 - 2² = 121078905919 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121078905823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2087567315 + ... + 2087567372.

It is an arithmetic number, because the mean of its divisors is an integer number (31313510160).

Almost surely, 2^121078905923 is an apocalyptic number.

121078905923 is a deficient number, since it is larger than the sum of its proper divisors (4175134717).

121078905923 is an equidigital number, since it uses as much as digits as its factorization.

121078905923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4175134716.

The product of its (nonzero) digits is 272160, while the sum is 47.

The spelling of 121078905923 in words is "one hundred twenty-one billion, seventy-eight million, nine hundred five thousand, nine hundred twenty-three".