21001021100210 has 8 divisors (see below), whose sum is σ = 37801837980396. Its totient is φ = 8400408440080.

The previous prime is 21001021100197. The next prime is 21001021100221. The reversal of 21001021100210 is 1200112010012.

It can be written as a sum of positive squares in 2 ways, for example, as 17089617013681 + 3911404086529 = 4133959^2 + 1977727^2 .

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

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21001021100191 and 21001021100200.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1050051055001 + ... + 1050051055020.

Almost surely, 2^{21001021100210} is an apocalyptic number.

21001021100210 is a deficient number, since it is larger than the sum of its proper divisors (16800816880186).

21001021100210 is a wasteful number, since it uses less digits than its factorization.

21001021100210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2100102110028.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21001021100210 its reverse (1200112010012), we get a palindrome (22201133110222).

The spelling of 21001021100210 in words is "twenty-one trillion, one billion, twenty-one million, one hundred thousand, two hundred ten".