86491997 has 2 divisors, whose sum is σ = 86491998. Its totient is φ = 86491996.

The previous prime is 86491981. The next prime is 86492017. The reversal of 86491997 is 79919468.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 47416996 + 39075001 = 6886^2 + 6251^2 .

It is a cyclic number.

It is not a de Polignac number, because 86491997 - 2⁴ = 86491981 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (86491907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43245998 + 43245999.

It is an arithmetic number, because the mean of its divisors is an integer number (43245999).

Almost surely, 2^86491997 is an apocalyptic number.

It is an amenable number.

86491997 is a deficient number, since it is larger than the sum of its proper divisors (1).

86491997 is an equidigital number, since it uses as much as digits as its factorization.

86491997 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 979776, while the sum is 53.

The square root of 86491997 is about 9300.1073649717. The cubic root of 86491997 is about 442.2406315152.

The spelling of 86491997 in words is "eighty-six million, four hundred ninety-one thousand, nine hundred ninety-seven".