21224635566 has 32 divisors (see below), whose sum is σ = 45130659840. Its totient is φ = 6639588384.

The previous prime is 21224635511. The next prime is 21224635571. The reversal of 21224635566 is 66553642212.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1443646 + ... + 1458273.

It is an arithmetic number, because the mean of its divisors is an integer number (1410333120).

Almost surely, 2^21224635566 is an apocalyptic number.

21224635566 is an abundant number, since it is smaller than the sum of its proper divisors (23906024274).

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

21224635566 is a wasteful number, since it uses less digits than its factorization.

21224635566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2902000.

The product of its digits is 518400, while the sum is 42.

The spelling of 21224635566 in words is "twenty-one billion, two hundred twenty-four million, six hundred thirty-five thousand, five hundred sixty-six".