21385635 has 16 divisors (see below), whose sum is σ = 34296480. Its totient is φ = 11379200.

The previous prime is 21385633. The next prime is 21385649. The reversal of 21385635 is 53658312.

It is not a de Polignac number, because 21385635 - 2¹ = 21385633 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 21385596 and 21385605.

It is not an unprimeable number, because it can be changed into a prime (21385633) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 6235 + ... + 9035.

It is an arithmetic number, because the mean of its divisors is an integer number (2143530).

Almost surely, 2^21385635 is an apocalyptic number.

21385635 is a deficient number, since it is larger than the sum of its proper divisors (12910845).

21385635 is a wasteful number, since it uses less digits than its factorization.

21385635 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3318.

The product of its digits is 21600, while the sum is 33.

The square root of 21385635 is about 4624.4605090756. The cubic root of 21385635 is about 277.5709744600.

The spelling of 21385635 in words is "twenty-one million, three hundred eighty-five thousand, six hundred thirty-five".