21001101202001 has 2 divisors, whose sum is σ = 21001101202002. Its totient is φ = 21001101202000.

The previous prime is 21001101201797. The next prime is 21001101202009. The reversal of 21001101202001 is 10020210110012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10809530206225 + 10191570995776 = 3287785^2 + 3192424^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21001101202001 is a prime.

It is not a weakly prime, because it can be changed into another prime (21001101202009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500550601000 + 10500550601001.

It is an arithmetic number, because the mean of its divisors is an integer number (10500550601001).

Almost surely, 2^{21001101202001} is an apocalyptic number.

It is an amenable number.

21001101202001 is a deficient number, since it is larger than the sum of its proper divisors (1).

21001101202001 is an equidigital number, since it uses as much as digits as its factorization.

21001101202001 is an odious number, because the sum of its binary digits is odd.

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

Adding to 21001101202001 its reverse (10020210110012), we get a palindrome (31021311312013).

The spelling of 21001101202001 in words is "twenty-one trillion, one billion, one hundred one million, two hundred two thousand, one".