121709409 has 8 divisors (see below), whose sum is σ = 171825120. Its totient is φ = 76366656.

The previous prime is 121709381. The next prime is 121709431. The reversal of 121709409 is 904907121.

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

It is not a de Polignac number, because 121709409 - 2⁷ = 121709281 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 121709409.

It is not an unprimeable number, because it can be changed into a prime (121709449) 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, 1193179 + ... + 1193280.

It is an arithmetic number, because the mean of its divisors is an integer number (21478140).

Almost surely, 2^121709409 is an apocalyptic number.

It is an amenable number.

121709409 is a deficient number, since it is larger than the sum of its proper divisors (50115711).

121709409 is a wasteful number, since it uses less digits than its factorization.

121709409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2386479.

The product of its (nonzero) digits is 4536, while the sum is 33.

The square root of 121709409 is about 11032.1987382389. The cubic root of 121709409 is about 495.5734726906.

The spelling of 121709409 in words is "one hundred twenty-one million, seven hundred nine thousand, four hundred nine".