21243004235 has 16 divisors (see below), whose sum is σ = 25637472000. Its totient is φ = 16897278816.

The previous prime is 21243004219. The next prime is 21243004241. The reversal of 21243004235 is 53240034212.

It is a cyclic number.

It is not a de Polignac number, because 21243004235 - 2⁴ = 21243004219 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1604312 + ... + 1617498.

It is an arithmetic number, because the mean of its divisors is an integer number (1602342000).

Almost surely, 2^21243004235 is an apocalyptic number.

21243004235 is a deficient number, since it is larger than the sum of its proper divisors (4394467765).

21243004235 is a wasteful number, since it uses less digits than its factorization.

21243004235 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15010.

The product of its (nonzero) digits is 5760, while the sum is 26.

Adding to 21243004235 its reverse (53240034212), we get a palindrome (74483038447).

The spelling of 21243004235 in words is "twenty-one billion, two hundred forty-three million, four thousand, two hundred thirty-five".