86819861 has 2 divisors, whose sum is σ = 86819862. Its totient is φ = 86819860.

The previous prime is 86819851. The next prime is 86819869. The reversal of 86819861 is 16891868.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 82919236 + 3900625 = 9106^2 + 1975^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-86819861 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (86819869) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43409930 + 43409931.

It is an arithmetic number, because the mean of its divisors is an integer number (43409931).

Almost surely, 2^86819861 is an apocalyptic number.

It is an amenable number.

86819861 is a deficient number, since it is larger than the sum of its proper divisors (1).

86819861 is an equidigital number, since it uses as much as digits as its factorization.

86819861 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 165888, while the sum is 47.

The square root of 86819861 is about 9317.7175853317. The cubic root of 86819861 is about 442.7987253751.

The spelling of 86819861 in words is "eighty-six million, eight hundred nineteen thousand, eight hundred sixty-one".