21210021304 has 16 divisors (see below), whose sum is σ = 42108130800. Its totient is φ = 9981186432.

The previous prime is 21210021299. The next prime is 21210021307. The reversal of 21210021304 is 40312001212.

It is a super-2 number, since 2×21210021304² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21210021307) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 77977884 + ... + 77978155.

It is an arithmetic number, because the mean of its divisors is an integer number (2631758175).

Almost surely, 2^21210021304 is an apocalyptic number.

It is an amenable number.

21210021304 is a deficient number, since it is larger than the sum of its proper divisors (20898109496).

21210021304 is a wasteful number, since it uses less digits than its factorization.

21210021304 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155956062 (or 155956058 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 21210021304 its reverse (40312001212), we get a palindrome (61522022516).

The spelling of 21210021304 in words is "twenty-one billion, two hundred ten million, twenty-one thousand, three hundred four".