121945575491 has 4 divisors (see below), whose sum is σ = 121952604072. Its totient is φ = 121938546912.

The previous prime is 121945575481. The next prime is 121945575497. The reversal of 121945575491 is 194575549121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 194575549121 = 421 ⋅462174701.

It is a cyclic number.

It is not a de Polignac number, because 121945575491 - 2¹⁴ = 121945559107 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121945575497) 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, 3488201 + ... + 3522986.

It is an arithmetic number, because the mean of its divisors is an integer number (30488151018).

Almost surely, 2^121945575491 is an apocalyptic number.

121945575491 is a deficient number, since it is larger than the sum of its proper divisors (7028581).

121945575491 is an equidigital number, since it uses as much as digits as its factorization.

121945575491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7028580.

The product of its digits is 2268000, while the sum is 53.

The spelling of 121945575491 in words is "one hundred twenty-one billion, nine hundred forty-five million, five hundred seventy-five thousand, four hundred ninety-one".