7218573818 has 12 divisors (see below), whose sum is σ = 11036023278. Its totient is φ = 3541184400.

The previous prime is 7218573811. The next prime is 7218573883. The reversal of 7218573818 is 8183758127.

It can be written as a sum of positive squares in 3 ways, for example, as 6340459129 + 878114689 = 79627^2 + 29633^2 .

It is not an unprimeable number, because it can be changed into a prime (7218573811) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 636833 + ... + 648068.

Almost surely, 2^7218573818 is an apocalyptic number.

7218573818 is a deficient number, since it is larger than the sum of its proper divisors (3817449460).

7218573818 is a wasteful number, since it uses less digits than its factorization.

7218573818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1285009 (or 1284956 counting only the distinct ones).

The product of its digits is 752640, while the sum is 50.

The square root of 7218573818 is about 84962.1905202544. The cubic root of 7218573818 is about 1932.6377901145.

The spelling of 7218573818 in words is "seven billion, two hundred eighteen million, five hundred seventy-three thousand, eight hundred eighteen".