21568997224 has 64 divisors (see below), whose sum is σ = 43824291840. Its totient is φ = 9922630080.

The previous prime is 21568997221. The next prime is 21568997273. The reversal of 21568997224 is 42279986512.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21568997221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 941247 + ... + 963889.

It is an arithmetic number, because the mean of its divisors is an integer number (684754560).

Almost surely, 2^21568997224 is an apocalyptic number.

It is an amenable number.

21568997224 is an abundant number, since it is smaller than the sum of its proper divisors (22255294616).

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

21568997224 is a wasteful number, since it uses less digits than its factorization.

21568997224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22870 (or 22866 counting only the distinct ones).

The product of its digits is 4354560, while the sum is 55.

The spelling of 21568997224 in words is "twenty-one billion, five hundred sixty-eight million, nine hundred ninety-seven thousand, two hundred twenty-four".