121022100091 has 4 divisors (see below), whose sum is σ = 122726636784. Its totient is φ = 119317563400.

The previous prime is 121022100079. The next prime is 121022100109. The reversal of 121022100091 is 190001220121.

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: 190001220121 = 4909 ⋅38704669.

It is a cyclic number.

It is not a de Polignac number, because 121022100091 - 2¹⁵ = 121022067323 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121022100061) 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, 852268240 + ... + 852268381.

It is an arithmetic number, because the mean of its divisors is an integer number (30681659196).

Almost surely, 2^121022100091 is an apocalyptic number.

121022100091 is a deficient number, since it is larger than the sum of its proper divisors (1704536693).

121022100091 is an equidigital number, since it uses as much as digits as its factorization.

121022100091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1704536692.

The product of its (nonzero) digits is 72, while the sum is 19.

The spelling of 121022100091 in words is "one hundred twenty-one billion, twenty-two million, one hundred thousand, ninety-one".