121838252091 has 4 divisors (see below), whose sum is σ = 162451002792. Its totient is φ = 81225501392.

The previous prime is 121838252087. The next prime is 121838252093. The reversal of 121838252091 is 190252838121.

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 121838252091 - 2² = 121838252087 is a prime.

It is not an unprimeable number, because it can be changed into a prime (121838252093) 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, 20306375346 + ... + 20306375351.

It is an arithmetic number, because the mean of its divisors is an integer number (40612750698).

Almost surely, 2^121838252091 is an apocalyptic number.

121838252091 is a deficient number, since it is larger than the sum of its proper divisors (40612750701).

121838252091 is an equidigital number, since it uses as much as digits as its factorization.

121838252091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40612750700.

The product of its (nonzero) digits is 69120, while the sum is 42.

The spelling of 121838252091 in words is "one hundred twenty-one billion, eight hundred thirty-eight million, two hundred fifty-two thousand, ninety-one".