218940717 has 8 divisors (see below), whose sum is σ = 293196640. Its totient is φ = 145322640.

The previous prime is 218940713. The next prime is 218940719. The reversal of 218940717 is 717049812.

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

It is not a de Polignac number, because 218940717 - 2² = 218940713 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218940713) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 158659 + ... + 160032.

It is an arithmetic number, because the mean of its divisors is an integer number (36649580).

Almost surely, 2^218940717 is an apocalyptic number.

It is an amenable number.

218940717 is a deficient number, since it is larger than the sum of its proper divisors (74255923).

218940717 is a wasteful number, since it uses less digits than its factorization.

218940717 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 318923.

The product of its (nonzero) digits is 28224, while the sum is 39.

The square root of 218940717 is about 14796.6454644288. The cubic root of 218940717 is about 602.7106218852.

The spelling of 218940717 in words is "two hundred eighteen million, nine hundred forty thousand, seven hundred seventeen".