21444442001 has 2 divisors, whose sum is σ = 21444442002. Its totient is φ = 21444442000.

The previous prime is 21444441947. The next prime is 21444442009. The reversal of 21444442001 is 10024444412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16449345025 + 4995096976 = 128255^2 + 70676^2 .

It is a cyclic number.

It is not a de Polignac number, because 21444442001 - 2²⁶ = 21377333137 is a prime.

It is not a weakly prime, because it can be changed into another prime (21444442009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10722221000 + 10722221001.

It is an arithmetic number, because the mean of its divisors is an integer number (10722221001).

Almost surely, 2^21444442001 is an apocalyptic number.

It is an amenable number.

21444442001 is a deficient number, since it is larger than the sum of its proper divisors (1).

21444442001 is an equidigital number, since it uses as much as digits as its factorization.

21444442001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4096, while the sum is 26.

Adding to 21444442001 its reverse (10024444412), we get a palindrome (31468886413).

The spelling of 21444442001 in words is "twenty-one billion, four hundred forty-four million, four hundred forty-two thousand, one".