82128647 has 2 divisors, whose sum is σ = 82128648. Its totient is φ = 82128646.

The previous prime is 82128619. The next prime is 82128707. The reversal of 82128647 is 74682128.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 82128647 - 2⁸ = 82128391 is a prime.

It is a super-2 number, since 2×82128647² = 13490229316101218, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 82128647.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (82128847) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41064323 + 41064324.

It is an arithmetic number, because the mean of its divisors is an integer number (41064324).

Almost surely, 2^82128647 is an apocalyptic number.

82128647 is a deficient number, since it is larger than the sum of its proper divisors (1).

82128647 is an equidigital number, since it uses as much as digits as its factorization.

82128647 is an evil number, because the sum of its binary digits is even.

The product of its digits is 43008, while the sum is 38.

The square root of 82128647 is about 9062.4856965404. The cubic root of 82128647 is about 434.6752268216.

The spelling of 82128647 in words is "eighty-two million, one hundred twenty-eight thousand, six hundred forty-seven".