21359636 has 18 divisors (see below), whose sum is σ = 38117982. Its totient is φ = 10472800.

The previous prime is 21359627. The next prime is 21359641. The reversal of 21359636 is 63695312.

It can be written as a sum of positive squares in 3 ways, for example, as 2869636 + 18490000 = 1694^2 + 4300^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21359596 and 21359605.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 10286 + ... + 12186.

Almost surely, 2^21359636 is an apocalyptic number.

It is an amenable number.

21359636 is a deficient number, since it is larger than the sum of its proper divisors (16758346).

21359636 is a wasteful number, since it uses less digits than its factorization.

21359636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2011 (or 1956 counting only the distinct ones).

The product of its digits is 29160, while the sum is 35.

The square root of 21359636 is about 4621.6486235974. The cubic root of 21359636 is about 277.4584457432.

The spelling of 21359636 in words is "twenty-one million, three hundred fifty-nine thousand, six hundred thirty-six".