39628482581 has 2 divisors, whose sum is σ = 39628482582. Its totient is φ = 39628482580.

The previous prime is 39628482577. The next prime is 39628482599. The reversal of 39628482581 is 18528482693.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 39557232100 + 71250481 = 198890^2 + 8441^2 .

It is a cyclic number.

It is not a de Polignac number, because 39628482581 - 2² = 39628482577 is a prime.

It is a super-2 number, since 2×39628482581² (a number of 22 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (39628482781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19814241290 + 19814241291.

It is an arithmetic number, because the mean of its divisors is an integer number (19814241291).

Almost surely, 2^39628482581 is an apocalyptic number.

It is an amenable number.

39628482581 is a deficient number, since it is larger than the sum of its proper divisors (1).

39628482581 is an equidigital number, since it uses as much as digits as its factorization.

39628482581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6635520, while the sum is 56.

The spelling of 39628482581 in words is "thirty-nine billion, six hundred twenty-eight million, four hundred eighty-two thousand, five hundred eighty-one".