82756021 has 2 divisors, whose sum is σ = 82756022. Its totient is φ = 82756020.

The previous prime is 82756007. The next prime is 82756031. The reversal of 82756021 is 12065728.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 72063121 + 10692900 = 8489^2 + 3270^2 .

It is a cyclic number.

It is not a de Polignac number, because 82756021 - 2⁵ = 82755989 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (82756031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41378010 + 41378011.

It is an arithmetic number, because the mean of its divisors is an integer number (41378011).

Almost surely, 2^82756021 is an apocalyptic number.

It is an amenable number.

82756021 is a deficient number, since it is larger than the sum of its proper divisors (1).

82756021 is an equidigital number, since it uses as much as digits as its factorization.

82756021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 82756021 is about 9097.0336374007. The cubic root of 82756021 is about 435.7792365672.

The spelling of 82756021 in words is "eighty-two million, seven hundred fifty-six thousand, twenty-one".