121049891 has 4 divisors (see below), whose sum is σ = 121072800. Its totient is φ = 121026984.

The previous prime is 121049881. The next prime is 121049899. The reversal of 121049891 is 198940121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 198940121 = 349 ⋅570029.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121049891 is a prime.

It is a super-2 number, since 2×121049891² = 29306152222223762, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121049899) 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, 950 + ... + 15588.

It is an arithmetic number, because the mean of its divisors is an integer number (30268200).

Almost surely, 2^121049891 is an apocalyptic number.

121049891 is a deficient number, since it is larger than the sum of its proper divisors (22909).

121049891 is an equidigital number, since it uses as much as digits as its factorization.

121049891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22908.

The product of its (nonzero) digits is 5184, while the sum is 35.

The square root of 121049891 is about 11002.2675390121. The cubic root of 121049891 is about 494.6767143912.

The spelling of 121049891 in words is "one hundred twenty-one million, forty-nine thousand, eight hundred ninety-one".