218138421770857 has 16 divisors (see below), whose sum is σ = 250684360698240. Its totient is φ = 185941125076608.

The previous prime is 218138421770839. The next prime is 218138421770869. The reversal of 218138421770857 is 758077124831812.

It is a cyclic number.

It is not a de Polignac number, because 218138421770857 - 2¹⁹ = 218138421246569 is a prime.

It is not an unprimeable number, because it can be changed into a prime (218138421770887) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 116379108 + ... + 118238629.

It is an arithmetic number, because the mean of its divisors is an integer number (15667772543640).

Almost surely, 2^{218138421770857} is an apocalyptic number.

It is an amenable number.

218138421770857 is a deficient number, since it is larger than the sum of its proper divisors (32545938927383).

218138421770857 is a wasteful number, since it uses less digits than its factorization.

218138421770857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234618480.

The product of its (nonzero) digits is 42147840, while the sum is 64.

The spelling of 218138421770857 in words is "two hundred eighteen trillion, one hundred thirty-eight billion, four hundred twenty-one million, seven hundred seventy thousand, eight hundred fifty-seven".