21505000045304 has 32 divisors (see below), whose sum is σ = 40809318858000. Its totient is φ = 10622525417472.

The previous prime is 21505000045297. The next prime is 21505000045327. The reversal of 21505000045304 is 40354000050512.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16234262 + ... + 17508890.

Almost surely, 2^{21505000045304} is an apocalyptic number.

It is an amenable number.

21505000045304 is a deficient number, since it is larger than the sum of its proper divisors (19304318812696).

21505000045304 is a wasteful number, since it uses less digits than its factorization.

21505000045304 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1300127 (or 1300123 counting only the distinct ones).

The product of its (nonzero) digits is 12000, while the sum is 29.

Adding to 21505000045304 its reverse (40354000050512), we get a palindrome (61859000095816).

The spelling of 21505000045304 in words is "twenty-one trillion, five hundred five billion, forty-five thousand, three hundred four".