16446001021 has 2 divisors, whose sum is σ = 16446001022. Its totient is φ = 16446001020.

The previous prime is 16446001009. The next prime is 16446001027. The reversal of 16446001021 is 12010064461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10968372900 + 5477628121 = 104730^2 + 74011^2 .

It is an emirp because it is prime and its reverse (12010064461) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16446001021 - 2²¹ = 16443903869 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16446001027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8223000510 + 8223000511.

It is an arithmetic number, because the mean of its divisors is an integer number (8223000511).

Almost surely, 2^16446001021 is an apocalyptic number.

It is an amenable number.

16446001021 is a deficient number, since it is larger than the sum of its proper divisors (1).

16446001021 is an equidigital number, since it uses as much as digits as its factorization.

16446001021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1152, while the sum is 25.

Adding to 16446001021 its reverse (12010064461), we get a palindrome (28456065482).

The spelling of 16446001021 in words is "sixteen billion, four hundred forty-six million, one thousand, twenty-one".