21201444001009 has 2 divisors, whose sum is σ = 21201444001010. Its totient is φ = 21201444001008.

The previous prime is 21201444000991. The next prime is 21201444001061. The reversal of 21201444001009 is 90010044410212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19542765318400 + 1658678682609 = 4420720^2 + 1287897^2 .

It is a cyclic number.

It is not a de Polignac number, because 21201444001009 - 2⁵ = 21201444000977 is a prime.

It is not a weakly prime, because it can be changed into another prime (21201444001099) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10600722000504 + 10600722000505.

It is an arithmetic number, because the mean of its divisors is an integer number (10600722000505).

Almost surely, 2^{21201444001009} is an apocalyptic number.

It is an amenable number.

21201444001009 is a deficient number, since it is larger than the sum of its proper divisors (1).

21201444001009 is an equidigital number, since it uses as much as digits as its factorization.

21201444001009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 28.

The spelling of 21201444001009 in words is "twenty-one trillion, two hundred one billion, four hundred forty-four million, one thousand, nine".