21035630 has 64 divisors (see below), whose sum is σ = 50015232. Its totient is φ = 6167040.

The previous prime is 21035629. The next prime is 21035633. The reversal of 21035630 is 3653012.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21035633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12287 + ... + 13893.

It is an arithmetic number, because the mean of its divisors is an integer number (781488).

Almost surely, 2^21035630 is an apocalyptic number.

21035630 is an abundant number, since it is smaller than the sum of its proper divisors (28979602).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21035630 is a wasteful number, since it uses less digits than its factorization.

21035630 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1649.

The product of its (nonzero) digits is 540, while the sum is 20.

The square root of 21035630 is about 4586.4615990979. The cubic root of 21035630 is about 276.0483619657.

Adding to 21035630 its reverse (3653012), we get a palindrome (24688642).

The spelling of 21035630 in words is "twenty-one million, thirty-five thousand, six hundred thirty".