121818815 has 8 divisors (see below), whose sum is σ = 147028608. Its totient is φ = 96891040.

The previous prime is 121818811. The next prime is 121818817. The reversal of 121818815 is 518818121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 121818815 - 2² = 121818811 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121818811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 69551 + ... + 71280.

It is an arithmetic number, because the mean of its divisors is an integer number (18378576).

Almost surely, 2^121818815 is an apocalyptic number.

121818815 is a deficient number, since it is larger than the sum of its proper divisors (25209793).

121818815 is a wasteful number, since it uses less digits than its factorization.

121818815 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141009.

The product of its digits is 5120, while the sum is 35.

The square root of 121818815 is about 11037.1561101581. The cubic root of 121818815 is about 495.7219204674.

The spelling of 121818815 in words is "one hundred twenty-one million, eight hundred eighteen thousand, eight hundred fifteen".