86171881 has 2 divisors, whose sum is σ = 86171882. Its totient is φ = 86171880.

The previous prime is 86171867. The next prime is 86171893. The reversal of 86171881 is 18817168.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 62552281 + 23619600 = 7909^2 + 4860^2 .

It is a cyclic number.

It is not a de Polignac number, because 86171881 - 2⁷ = 86171753 is a prime.

It is a super-2 number, since 2×86171881² = 14851186150156322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (86171831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43085940 + 43085941.

It is an arithmetic number, because the mean of its divisors is an integer number (43085941).

Almost surely, 2^86171881 is an apocalyptic number.

It is an amenable number.

86171881 is a deficient number, since it is larger than the sum of its proper divisors (1).

86171881 is an equidigital number, since it uses as much as digits as its factorization.

86171881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21504, while the sum is 40.

The square root of 86171881 is about 9282.8810721672. The cubic root of 86171881 is about 441.6943639606.

The spelling of 86171881 in words is "eighty-six million, one hundred seventy-one thousand, eight hundred eighty-one".