21210485 has 16 divisors (see below), whose sum is σ = 26732160. Its totient is φ = 16125120.

The previous prime is 21210463. The next prime is 21210487. The reversal of 21210485 is 58401212.

It is not a de Polignac number, because 21210485 - 2²⁰ = 20161909 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21210485.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21210487) 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 15 ways as a sum of consecutive naturals, for example, 20306 + ... + 21324.

It is an arithmetic number, because the mean of its divisors is an integer number (1670760).

Almost surely, 2^21210485 is an apocalyptic number.

It is an amenable number.

21210485 is a deficient number, since it is larger than the sum of its proper divisors (5521675).

21210485 is a wasteful number, since it uses less digits than its factorization.

21210485 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1228.

The product of its (nonzero) digits is 640, while the sum is 23.

The square root of 21210485 is about 4605.4842307840. The cubic root of 21210485 is about 276.8111203516.

Adding to 21210485 its reverse (58401212), we get a palindrome (79611697).

The spelling of 21210485 in words is "twenty-one million, two hundred ten thousand, four hundred eighty-five".