21101002210 has 16 divisors (see below), whose sum is σ = 37983950136. Its totient is φ = 8439923968.

The previous prime is 21101002199. The next prime is 21101002249. The reversal of 21101002210 is 1220010112.

It can be written as a sum of positive squares in 4 ways, for example, as 17398401409 + 3702600801 = 131903^2 + 60849^2 .

It is a Harshad number since it is a multiple of its sum of digits (10).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 167364 + ... + 264976.

Almost surely, 2^21101002210 is an apocalyptic number.

21101002210 is a deficient number, since it is larger than the sum of its proper divisors (16882947926).

21101002210 is a wasteful number, since it uses less digits than its factorization.

21101002210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 119237.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 21101002210 its reverse (1220010112), we get a palindrome (22321012322).

The spelling of 21101002210 in words is "twenty-one billion, one hundred one million, two thousand, two hundred ten".