21818175648 has 24 divisors (see below), whose sum is σ = 57272711328. Its totient is φ = 7272725184.

The previous prime is 21818175611. The next prime is 21818175661. The reversal of 21818175648 is 84657181812.

It is a tau number, because it is divible by the number of its divisors (24).

It is a self number, because there is not a number n which added to its sum of digits gives 21818175648.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 113636236 + ... + 113636427.

It is an arithmetic number, because the mean of its divisors is an integer number (2386362972).

Almost surely, 2^21818175648 is an apocalyptic number.

It is an amenable number.

21818175648 is an abundant number, since it is smaller than the sum of its proper divisors (35454535680).

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

21818175648 is a wasteful number, since it uses less digits than its factorization.

21818175648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 227272676 (or 227272668 counting only the distinct ones).

The product of its digits is 860160, while the sum is 51.

The spelling of 21818175648 in words is "twenty-one billion, eight hundred eighteen million, one hundred seventy-five thousand, six hundred forty-eight".