81000487 has 2 divisors, whose sum is σ = 81000488. Its totient is φ = 81000486.

The previous prime is 81000481. The next prime is 81000523. The reversal of 81000487 is 78400018.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81000487 - 2¹⁹ = 80476199 is a prime.

It is a super-2 number, since 2×81000487² = 13122157788474338, which contains 22 as substring.

It is equal to p_4724443 and since 81000487 and 4724443 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81000481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40500243 + 40500244.

It is an arithmetic number, because the mean of its divisors is an integer number (40500244).

Almost surely, 2^81000487 is an apocalyptic number.

81000487 is a deficient number, since it is larger than the sum of its proper divisors (1).

81000487 is an equidigital number, since it uses as much as digits as its factorization.

81000487 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1792, while the sum is 28.

The square root of 81000487 is about 9000.0270555149. The cubic root of 81000487 is about 432.6757382208.

The spelling of 81000487 in words is "eighty-one million, four hundred eighty-seven", and thus it is an aban number.