121756217 has 8 divisors (see below), whose sum is σ = 133412832. Its totient is φ = 110197600.

The previous prime is 121756171. The next prime is 121756223. The reversal of 121756217 is 712657121.

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 121756217 - 2²⁴ = 104979001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121756417) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21884 + ... + 26877.

It is an arithmetic number, because the mean of its divisors is an integer number (16676604).

Almost surely, 2^121756217 is an apocalyptic number.

It is an amenable number.

121756217 is a deficient number, since it is larger than the sum of its proper divisors (11656615).

121756217 is a wasteful number, since it uses less digits than its factorization.

121756217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48999.

The product of its digits is 5880, while the sum is 32.

The square root of 121756217 is about 11034.3199609219. The cubic root of 121756217 is about 495.6369951145.

The spelling of 121756217 in words is "one hundred twenty-one million, seven hundred fifty-six thousand, two hundred seventeen".