82170661 has 2 divisors, whose sum is σ = 82170662. Its totient is φ = 82170660.

The previous prime is 82170653. The next prime is 82170679. The reversal of 82170661 is 16607128.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 71081761 + 11088900 = 8431^2 + 3330^2 .

It is a cyclic number.

It is not a de Polignac number, because 82170661 - 2³ = 82170653 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (82170161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41085330 + 41085331.

It is an arithmetic number, because the mean of its divisors is an integer number (41085331).

Almost surely, 2^82170661 is an apocalyptic number.

It is an amenable number.

82170661 is a deficient number, since it is larger than the sum of its proper divisors (1).

82170661 is an equidigital number, since it uses as much as digits as its factorization.

82170661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 82170661 is about 9064.8034176147. The cubic root of 82170661 is about 434.7493354808.

Adding to 82170661 its reverse (16607128), we get a palindrome (98777789).

The spelling of 82170661 in words is "eighty-two million, one hundred seventy thousand, six hundred sixty-one".