16825944581 has 2 divisors, whose sum is σ = 16825944582. Its totient is φ = 16825944580.

The previous prime is 16825944557. The next prime is 16825944673. The reversal of 16825944581 is 18544952861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12948391681 + 3877552900 = 113791^2 + 62270^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16825944581 is a prime.

It is a super-2 number, since 2×16825944581² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16825944511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8412972290 + 8412972291.

It is an arithmetic number, because the mean of its divisors is an integer number (8412972291).

Almost surely, 2^16825944581 is an apocalyptic number.

It is an amenable number.

16825944581 is a deficient number, since it is larger than the sum of its proper divisors (1).

16825944581 is an equidigital number, since it uses as much as digits as its factorization.

16825944581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2764800, while the sum is 53.

The spelling of 16825944581 in words is "sixteen billion, eight hundred twenty-five million, nine hundred forty-four thousand, five hundred eighty-one".