121816906 has 8 divisors (see below), whose sum is σ = 183196260. Its totient is φ = 60751488.

The previous prime is 121816897. The next prime is 121816931. The reversal of 121816906 is 609618121.

It can be written as a sum of positive squares in 2 ways, for example, as 110986225 + 10830681 = 10535^2 + 3291^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 77511 + ... + 79066.

Almost surely, 2^121816906 is an apocalyptic number.

121816906 is a deficient number, since it is larger than the sum of its proper divisors (61379354).

121816906 is a wasteful number, since it uses less digits than its factorization.

121816906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156968.

The product of its (nonzero) digits is 5184, while the sum is 34.

The square root of 121816906 is about 11037.0696292087. The cubic root of 121816906 is about 495.7193309985.

The spelling of 121816906 in words is "one hundred twenty-one million, eight hundred sixteen thousand, nine hundred six".