21165537304 has 8 divisors (see below), whose sum is σ = 39685382460. Its totient is φ = 10582768648.

The previous prime is 21165537209. The next prime is 21165537329. The reversal of 21165537304 is 40373556112.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1322846074 + ... + 1322846089.

Almost surely, 2^21165537304 is an apocalyptic number.

It is an amenable number.

21165537304 is a deficient number, since it is larger than the sum of its proper divisors (18519845156).

21165537304 is a wasteful number, since it uses less digits than its factorization.

21165537304 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2645692169 (or 2645692165 counting only the distinct ones).

The product of its (nonzero) digits is 75600, while the sum is 37.

The spelling of 21165537304 in words is "twenty-one billion, one hundred sixty-five million, five hundred thirty-seven thousand, three hundred four".