21002102210 has 16 divisors (see below), whose sum is σ = 37820398392. Its totient is φ = 8397148800.

The previous prime is 21002102207. The next prime is 21002102213. The reversal of 21002102210 is 1220120012.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21002102207) and next prime (21002102213).

It can be written as a sum of positive squares in 4 ways, for example, as 17984687449 + 3017414761 = 134107^2 + 54931^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21002102191 and 21002102200.

It is not an unprimeable number, because it can be changed into a prime (21002102213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 437561 + ... + 483180.

Almost surely, 2^21002102210 is an apocalyptic number.

21002102210 is a deficient number, since it is larger than the sum of its proper divisors (16818296182).

21002102210 is a wasteful number, since it uses less digits than its factorization.

21002102210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 923029.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 21002102210 its reverse (1220120012), we get a palindrome (22222222222).

The spelling of 21002102210 in words is "twenty-one billion, two million, one hundred two thousand, two hundred ten".