21485225818 has 16 divisors (see below), whose sum is σ = 37730153664. Its totient is φ = 8983369440.

The previous prime is 21485225743. The next prime is 21485225833. The reversal of 21485225818 is 81852258412.

It is a super-2 number, since 2×21485225818² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18714780 + ... + 18715927.

It is an arithmetic number, because the mean of its divisors is an integer number (2358134604).

Almost surely, 2^21485225818 is an apocalyptic number.

21485225818 is a deficient number, since it is larger than the sum of its proper divisors (16244927846).

21485225818 is a wasteful number, since it uses less digits than its factorization.

21485225818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37430757.

The product of its digits is 409600, while the sum is 46.

The spelling of 21485225818 in words is "twenty-one billion, four hundred eighty-five million, two hundred twenty-five thousand, eight hundred eighteen".