21840822618 has 16 divisors (see below), whose sum is σ = 43821206976. Its totient is φ = 7257013920.

The previous prime is 21840822613. The next prime is 21840822637. The reversal of 21840822618 is 81622804812.

It is a self number, because there is not a number n which added to its sum of digits gives 21840822618.

It is not an unprimeable number, because it can be changed into a prime (21840822613) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5813038 + ... + 5816793.

It is an arithmetic number, because the mean of its divisors is an integer number (2738825436).

Almost surely, 2^21840822618 is an apocalyptic number.

21840822618 is an abundant number, since it is smaller than the sum of its proper divisors (21980384358).

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

21840822618 is a wasteful number, since it uses less digits than its factorization.

21840822618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11630149.

The product of its (nonzero) digits is 98304, while the sum is 42.

The spelling of 21840822618 in words is "twenty-one billion, eight hundred forty million, eight hundred twenty-two thousand, six hundred eighteen".