21211011020401 has 2 divisors, whose sum is σ = 21211011020402. Its totient is φ = 21211011020400.

The previous prime is 21211011020389. The next prime is 21211011020431. The reversal of 21211011020401 is 10402011011212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15548629080625 + 5662381939776 = 3943175^2 + 2379576^2 .

It is a cyclic number.

It is not a de Polignac number, because 21211011020401 - 2²⁹ = 21210474149489 is a prime.

It is not a weakly prime, because it can be changed into another prime (21211011020431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605505510200 + 10605505510201.

It is an arithmetic number, because the mean of its divisors is an integer number (10605505510201).

Almost surely, 2^{21211011020401} is an apocalyptic number.

It is an amenable number.

21211011020401 is a deficient number, since it is larger than the sum of its proper divisors (1).

21211011020401 is an equidigital number, since it uses as much as digits as its factorization.

21211011020401 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21211011020401 its reverse (10402011011212), we get a palindrome (31613022031613).

The spelling of 21211011020401 in words is "twenty-one trillion, two hundred eleven billion, eleven million, twenty thousand, four hundred one".