21145210 has 16 divisors (see below), whose sum is σ = 38151936. Its totient is φ = 8437968.

The previous prime is 21145199. The next prime is 21145213. The reversal of 21145210 is 1254112.

It is a super-3 number, since 3×21145210³ (a number of 23 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (21145213) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2347 + ... + 6913.

It is an arithmetic number, because the mean of its divisors is an integer number (2384496).

Almost surely, 2^21145210 is an apocalyptic number.

21145210 is a deficient number, since it is larger than the sum of its proper divisors (17006726).

21145210 is a wasteful number, since it uses less digits than its factorization.

21145210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5037.

The product of its (nonzero) digits is 80, while the sum is 16.

The square root of 21145210 is about 4598.3921102925. The cubic root of 21145210 is about 276.5268676470.

Adding to 21145210 its reverse (1254112), we get a palindrome (22399322).

The spelling of 21145210 in words is "twenty-one million, one hundred forty-five thousand, two hundred ten".