21002210 has 8 divisors (see below), whose sum is σ = 37803996. Its totient is φ = 8400880.

The previous prime is 21002207. The next prime is 21002213. The reversal of 21002210 is 1220012.

It is an interprime number because it is at equal distance from previous prime (21002207) and next prime (21002213).

It can be written as a sum of positive squares in 2 ways, for example, as 20967241 + 34969 = 4579^2 + 187^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (21002213) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1050101 + ... + 1050120.

Almost surely, 2^21002210 is an apocalyptic number.

21002210 is a deficient number, since it is larger than the sum of its proper divisors (16801786).

21002210 is a wasteful number, since it uses less digits than its factorization.

21002210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2100228.

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

The square root of 21002210 is about 4582.8168193808. The cubic root of 21002210 is about 275.9020954295.

Adding to 21002210 its reverse (1220012), we get a palindrome (22222222).

It can be divided in two parts, 21002 and 210, that added together give a palindrome (21212).

The spelling of 21002210 in words is "twenty-one million, two thousand, two hundred ten".