121819091 has 4 divisors (see below), whose sum is σ = 122450472. Its totient is φ = 121187712.

The previous prime is 121819081. The next prime is 121819123. The reversal of 121819091 is 190918121.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121819091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121819021) 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, 315401 + ... + 315786.

It is an arithmetic number, because the mean of its divisors is an integer number (30612618).

Almost surely, 2^121819091 is an apocalyptic number.

121819091 is a deficient number, since it is larger than the sum of its proper divisors (631381).

121819091 is an equidigital number, since it uses as much as digits as its factorization.

121819091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 631380.

The product of its (nonzero) digits is 1296, while the sum is 32.

The square root of 121819091 is about 11037.1686133718. The cubic root of 121819091 is about 495.7222948462.

The spelling of 121819091 in words is "one hundred twenty-one million, eight hundred nineteen thousand, ninety-one".