218480639 has 8 divisors (see below), whose sum is σ = 247670640. Its totient is φ = 191059776.

The previous prime is 218480629. The next prime is 218480659. The reversal of 218480639 is 936084812.

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 218480639 - 2²⁴ = 201703423 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 218480596 and 218480605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218480609) 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, 442022 + ... + 442515.

It is an arithmetic number, because the mean of its divisors is an integer number (30958830).

Almost surely, 2^218480639 is an apocalyptic number.

218480639 is a deficient number, since it is larger than the sum of its proper divisors (29190001).

218480639 is a wasteful number, since it uses less digits than its factorization.

218480639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 884569.

The product of its (nonzero) digits is 82944, while the sum is 41.

The square root of 218480639 is about 14781.0905889924. The cubic root of 218480639 is about 602.2881508135.

The spelling of 218480639 in words is "two hundred eighteen million, four hundred eighty thousand, six hundred thirty-nine".