21244040101 has 2 divisors, whose sum is σ = 21244040102. Its totient is φ = 21244040100.

The previous prime is 21244040071. The next prime is 21244040113. The reversal of 21244040101 is 10104044212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20837211201 + 406828900 = 144351^2 + 20170^2 .

It is a cyclic number.

It is not a de Polignac number, because 21244040101 - 2⁹ = 21244039589 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21244040141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10622020050 + 10622020051.

It is an arithmetic number, because the mean of its divisors is an integer number (10622020051).

Almost surely, 2^21244040101 is an apocalyptic number.

It is an amenable number.

21244040101 is a deficient number, since it is larger than the sum of its proper divisors (1).

21244040101 is an equidigital number, since it uses as much as digits as its factorization.

21244040101 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 256, while the sum is 19.

Adding to 21244040101 its reverse (10104044212), we get a palindrome (31348084313).

The spelling of 21244040101 in words is "twenty-one billion, two hundred forty-four million, forty thousand, one hundred one".