121638817 has 8 divisors (see below), whose sum is σ = 128296160. Its totient is φ = 115007040.

The previous prime is 121638809. The next prime is 121638827. The reversal of 121638817 is 718836121.

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 121638817 - 2³ = 121638809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121638827) 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, 3817 + ... + 16057.

It is an arithmetic number, because the mean of its divisors is an integer number (16037020).

Almost surely, 2^121638817 is an apocalyptic number.

It is an amenable number.

121638817 is a deficient number, since it is larger than the sum of its proper divisors (6657343).

121638817 is a wasteful number, since it uses less digits than its factorization.

121638817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12783.

The product of its digits is 16128, while the sum is 37.

The square root of 121638817 is about 11028.9989119593. The cubic root of 121638817 is about 495.4776425529.

The spelling of 121638817 in words is "one hundred twenty-one million, six hundred thirty-eight thousand, eight hundred seventeen".