218156954779 has 4 divisors (see below), whose sum is σ = 223230372376. Its totient is φ = 213083537184.

The previous prime is 218156954773. The next prime is 218156954803. The reversal of 218156954779 is 977459651812.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 218156954779 - 2¹⁷ = 218156823707 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 218156954779.

It is not an unprimeable number, because it can be changed into a prime (218156954773) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2536708734 + ... + 2536708819.

It is an arithmetic number, because the mean of its divisors is an integer number (55807593094).

Almost surely, 2^218156954779 is an apocalyptic number.

218156954779 is a deficient number, since it is larger than the sum of its proper divisors (5073417597).

218156954779 is an equidigital number, since it uses as much as digits as its factorization.

218156954779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5073417596.

The product of its digits is 38102400, while the sum is 64.

The spelling of 218156954779 in words is "two hundred eighteen billion, one hundred fifty-six million, nine hundred fifty-four thousand, seven hundred seventy-nine".