21220010 has 16 divisors (see below), whose sum is σ = 43652736. Its totient is φ = 7275408.

The previous prime is 21219997. The next prime is 21220019. The reversal of 21220010 is 1002212.

It is a self number, because there is not a number n which added to its sum of digits gives 21220010.

It is not an unprimeable number, because it can be changed into a prime (21220019) 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, 151502 + ... + 151641.

It is an arithmetic number, because the mean of its divisors is an integer number (2728296).

Almost surely, 2^21220010 is an apocalyptic number.

21220010 is an abundant number, since it is smaller than the sum of its proper divisors (22432726).

21220010 is a wasteful number, since it uses less digits than its factorization.

21220010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 303157.

The product of its (nonzero) digits is 8, while the sum is 8.

The square root of 21220010 is about 4606.5182079310. The cubic root of 21220010 is about 276.8525500399.

Adding to 21220010 its reverse (1002212), we get a palindrome (22222222).

The spelling of 21220010 in words is "twenty-one million, two hundred twenty thousand, ten".