121243809 has 8 divisors (see below), whose sum is σ = 167232960. Its totient is φ = 78041936.

The previous prime is 121243781. The next prime is 121243819. The reversal of 121243809 is 908342121.

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

It is a cyclic number.

It is not a de Polignac number, because 121243809 - 2⁵ = 121243777 is a prime.

It is a super-2 number, since 2×121243809² = 29400122441656962, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (121243819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 696717 + ... + 696890.

It is an arithmetic number, because the mean of its divisors is an integer number (20904120).

Almost surely, 2^121243809 is an apocalyptic number.

It is an amenable number.

121243809 is a deficient number, since it is larger than the sum of its proper divisors (45989151).

121243809 is a wasteful number, since it uses less digits than its factorization.

121243809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1393639.

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 121243809 is about 11011.0766503553. The cubic root of 121243809 is about 494.9407254807.

The spelling of 121243809 in words is "one hundred twenty-one million, two hundred forty-three thousand, eight hundred nine".