21210675 has 12 divisors (see below), whose sum is σ = 35068440. Its totient is φ = 11312320.

The previous prime is 21210649. The next prime is 21210691. The reversal of 21210675 is 57601212.

It is not a de Polignac number, because 21210675 - 2¹² = 21206579 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 141330 + ... + 141479.

It is an arithmetic number, because the mean of its divisors is an integer number (2922370).

Almost surely, 2^21210675 is an apocalyptic number.

21210675 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21210675 is a deficient number, since it is larger than the sum of its proper divisors (13857765).

21210675 is a wasteful number, since it uses less digits than its factorization.

21210675 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 282822 (or 282817 counting only the distinct ones).

The product of its (nonzero) digits is 840, while the sum is 24.

The square root of 21210675 is about 4605.5048583190. The cubic root of 21210675 is about 276.8119468918.

Adding to 21210675 its reverse (57601212), we get a palindrome (78811887).

The spelling of 21210675 in words is "twenty-one million, two hundred ten thousand, six hundred seventy-five".