218972655 has 48 divisors (see below), whose sum is σ = 415812384. Its totient is φ = 105719040.

The previous prime is 218972639. The next prime is 218972681. The reversal of 218972655 is 556279812.

It is not a de Polignac number, because 218972655 - 2⁴ = 218972639 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 218972655.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 136317 + ... + 137913.

It is an arithmetic number, because the mean of its divisors is an integer number (8662758).

Almost surely, 2^218972655 is an apocalyptic number.

218972655 is a deficient number, since it is larger than the sum of its proper divisors (196839729).

218972655 is a wasteful number, since it uses less digits than its factorization.

218972655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1896 (or 1893 counting only the distinct ones).

The product of its digits is 302400, while the sum is 45.

The square root of 218972655 is about 14797.7246561760. The cubic root of 218972655 is about 602.7399272852.

The spelling of 218972655 in words is "two hundred eighteen million, nine hundred seventy-two thousand, six hundred fifty-five".