21815084446 has 16 divisors (see below), whose sum is σ = 33287108400. Its totient is φ = 10719491328.

The previous prime is 21815084399. The next prime is 21815084453. The reversal of 21815084446 is 64448051812.

21815084446 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×21815084446² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 400750 + ... + 451918.

It is an arithmetic number, because the mean of its divisors is an integer number (2080444275).

Almost surely, 2^21815084446 is an apocalyptic number.

21815084446 is a deficient number, since it is larger than the sum of its proper divisors (11472023954).

21815084446 is a wasteful number, since it uses less digits than its factorization.

21815084446 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54843.

The product of its (nonzero) digits is 245760, while the sum is 43.

The spelling of 21815084446 in words is "twenty-one billion, eight hundred fifteen million, eighty-four thousand, four hundred forty-six".