21661135304 has 16 divisors (see below), whose sum is σ = 40616502300. Its totient is φ = 10830068032.

The previous prime is 21661135297. The next prime is 21661135337. The reversal of 21661135304 is 40353116612.

It can be written as a sum of positive squares in 2 ways, for example, as 20428984900 + 1232150404 = 142930^2 + 35102^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 174842 + ... + 271830.

Almost surely, 2^21661135304 is an apocalyptic number.

It is an amenable number.

21661135304 is a deficient number, since it is larger than the sum of its proper divisors (18955366996).

21661135304 is a wasteful number, since it uses less digits than its factorization.

21661135304 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124912 (or 124908 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 32.

The spelling of 21661135304 in words is "twenty-one billion, six hundred sixty-one million, one hundred thirty-five thousand, three hundred four".