21304233530 has 32 divisors (see below), whose sum is σ = 38999111040. Its totient is φ = 8377081920.

The previous prime is 21304233473. The next prime is 21304233539. The reversal of 21304233530 is 3533240312.

It is a happy number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21304233530.

It is not an unprimeable number, because it can be changed into a prime (21304233539) 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, 1136897 + ... + 1155483.

It is an arithmetic number, because the mean of its divisors is an integer number (1218722220).

Almost surely, 2^21304233530 is an apocalyptic number.

21304233530 is a deficient number, since it is larger than the sum of its proper divisors (17694877510).

21304233530 is a wasteful number, since it uses less digits than its factorization.

21304233530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20534.

The product of its (nonzero) digits is 6480, while the sum is 26.

Adding to 21304233530 its reverse (3533240312), we get a palindrome (24837473842).

The spelling of 21304233530 in words is "twenty-one billion, three hundred four million, two hundred thirty-three thousand, five hundred thirty".