21243220304 has 20 divisors (see below), whose sum is σ = 41405204064. Its totient is φ = 10558006368.

The previous prime is 21243220267. The next prime is 21243220373. The reversal of 21243220304 is 40302234212.

It is a self number, because there is not a number n which added to its sum of digits gives 21243220304.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3972482 + ... + 3977825.

Almost surely, 2^21243220304 is an apocalyptic number.

It is an amenable number.

21243220304 is a deficient number, since it is larger than the sum of its proper divisors (20161983760).

21243220304 is a wasteful number, since it uses less digits than its factorization.

21243220304 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7950482 (or 7950476 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 23.

Adding to 21243220304 its reverse (40302234212), we get a palindrome (61545454516).

The spelling of 21243220304 in words is "twenty-one billion, two hundred forty-three million, two hundred twenty thousand, three hundred four".