816187781618 has 32 divisors (see below), whose sum is σ = 1359426602880. Its totient is φ = 364409248000.

The previous prime is 816187781543. The next prime is 816187781623.

816187781618 is nontrivially palindromic in base 10.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 551063 + ... + 1391418.

It is an arithmetic number, because the mean of its divisors is an integer number (42482081340).

Almost surely, 2^816187781618 is an apocalyptic number.

816187781618 is a deficient number, since it is larger than the sum of its proper divisors (543238821262).

816187781618 is a wasteful number, since it uses less digits than its factorization.

816187781618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1942834.

The product of its digits is 7225344, while the sum is 62.

The spelling of 816187781618 in words is "eight hundred sixteen billion, one hundred eighty-seven million, seven hundred eighty-one thousand, six hundred eighteen".