21821447366 has 16 divisors (see below), whose sum is σ = 33472865088. Its totient is φ = 10665345600.

The previous prime is 21821447357. The next prime is 21821447377. The reversal of 21821447366 is 66374412812.

It is a happy number.

It is a congruent number.

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, 351095 + ... + 408546.

It is an arithmetic number, because the mean of its divisors is an integer number (2092054068).

Almost surely, 2^21821447366 is an apocalyptic number.

21821447366 is a deficient number, since it is larger than the sum of its proper divisors (11651417722).

21821447366 is a wasteful number, since it uses less digits than its factorization.

21821447366 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 759967.

The product of its digits is 387072, while the sum is 44.

The spelling of 21821447366 in words is "twenty-one billion, eight hundred twenty-one million, four hundred forty-seven thousand, three hundred sixty-six".