21021110201 has 24 divisors (see below), whose sum is σ = 27242235720. Its totient is φ = 16058552832.

The previous prime is 21021110197. The next prime is 21021110239. The reversal of 21021110201 is 10201112012.

It can be written as a sum of positive squares in 4 ways, for example, as 4147360000 + 16873750201 = 64400^2 + 129899^2 .

It is not a de Polignac number, because 21021110201 - 2² = 21021110197 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21021110281) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 550496 + ... + 587441.

It is an arithmetic number, because the mean of its divisors is an integer number (1135093155).

Almost surely, 2^21021110201 is an apocalyptic number.

It is an amenable number.

21021110201 is a deficient number, since it is larger than the sum of its proper divisors (6221125519).

21021110201 is a wasteful number, since it uses less digits than its factorization.

21021110201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1137993 (or 1137986 counting only the distinct ones).

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

Adding to 21021110201 its reverse (10201112012), we get a palindrome (31222222213).

The spelling of 21021110201 in words is "twenty-one billion, twenty-one million, one hundred ten thousand, two hundred one".