216222825618 has 54 divisors (see below), whose sum is σ = 472748471559. Its totient is φ = 71423902872.

The previous prime is 216222825617. The next prime is 216222825697. The reversal of 216222825618 is 816528222612.

216222825618 is a `hidden beast` number, since 2 + 1 + 6 + 2 + 2 + 2 + 8 + 25 + 618 = 666.

It can be written as a sum of positive squares in only one way, i.e., 108111412809 + 108111412809 = 328803^2 + 328803^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=328803.

It is not an unprimeable number, because it can be changed into a prime (216222825617) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 250547455 + ... + 250548317.

Almost surely, 2^216222825618 is an apocalyptic number.

216222825618 is an abundant number, since it is smaller than the sum of its proper divisors (256525645941).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

216222825618 is an frugal number, since it uses more digits than its factorization.

216222825618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1988 (or 995 counting only the distinct ones).

The product of its digits is 368640, while the sum is 45.

The spelling of 216222825618 in words is "two hundred sixteen billion, two hundred twenty-two million, eight hundred twenty-five thousand, six hundred eighteen".