81000697 has 2 divisors, whose sum is σ = 81000698. Its totient is φ = 81000696.

The previous prime is 81000677. The next prime is 81000709. The reversal of 81000697 is 79600018.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 55890576 + 25110121 = 7476^2 + 5011^2 .

It is a cyclic number.

It is not a de Polignac number, because 81000697 - 2¹¹ = 80998649 is a prime.

It is a super-2 number, since 2×81000697² = 13122225828971618, which contains 22 as substring.

It is equal to p_4724455 and since 81000697 and 4724455 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (81000677) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40500348 + 40500349.

It is an arithmetic number, because the mean of its divisors is an integer number (40500349).

Almost surely, 2^81000697 is an apocalyptic number.

It is an amenable number.

81000697 is a deficient number, since it is larger than the sum of its proper divisors (1).

81000697 is an equidigital number, since it uses as much as digits as its factorization.

81000697 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3024, while the sum is 31.

The square root of 81000697 is about 9000.0387221389. The cubic root of 81000697 is about 432.6761121355.

The spelling of 81000697 in words is "eighty-one million, six hundred ninety-seven", and thus it is an aban number.