81097637 has 2 divisors, whose sum is σ = 81097638. Its totient is φ = 81097636.

The previous prime is 81097619. The next prime is 81097649. The reversal of 81097637 is 73679018.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 80174116 + 923521 = 8954^2 + 961^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81097637 is a prime.

It is equal to p_4729874 and since 81097637 and 4729874 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 81097594 and 81097603.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81097657) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40548818 + 40548819.

It is an arithmetic number, because the mean of its divisors is an integer number (40548819).

Almost surely, 2^81097637 is an apocalyptic number.

It is an amenable number.

81097637 is a deficient number, since it is larger than the sum of its proper divisors (1).

81097637 is an equidigital number, since it uses as much as digits as its factorization.

81097637 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 63504, while the sum is 41.

The square root of 81097637 is about 9005.4226441628. The cubic root of 81097637 is about 432.8486493381.

The spelling of 81097637 in words is "eighty-one million, ninety-seven thousand, six hundred thirty-seven".