21010100202001 has 2 divisors, whose sum is σ = 21010100202002. Its totient is φ = 21010100202000.

The previous prime is 21010100201999. The next prime is 21010100202011. The reversal of 21010100202001 is 10020200101012.

It is an a-pointer prime, because the next prime (21010100202011) can be obtained adding 21010100202001 to its sum of digits (10).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20899343696400 + 110756505601 = 4571580^2 + 332801^2 .

It is a cyclic number.

It is not a de Polignac number, because 21010100202001 - 2¹ = 21010100201999 is a prime.

It is a super-2 number, since 2×21010100202001² (a number of 27 digits) contains 22 as substring.

Together with 21010100201999, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (21010100202011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505050101000 + 10505050101001.

It is an arithmetic number, because the mean of its divisors is an integer number (10505050101001).

Almost surely, 2^{21010100202001} is an apocalyptic number.

It is an amenable number.

21010100202001 is a deficient number, since it is larger than the sum of its proper divisors (1).

21010100202001 is an equidigital number, since it uses as much as digits as its factorization.

21010100202001 is an evil number, because the sum of its binary digits is even.

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

Adding to 21010100202001 its reverse (10020200101012), we get a palindrome (31030300303013).

The spelling of 21010100202001 in words is "twenty-one trillion, ten billion, one hundred million, two hundred two thousand, one".