81973603 has 2 divisors, whose sum is σ = 81973604. Its totient is φ = 81973602.

The previous prime is 81973561. The next prime is 81973607. The reversal of 81973603 is 30637918.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81973603 is a prime.

It is a super-3 number, since 3×81973603³ (a number of 25 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (81973607) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40986801 + 40986802.

It is an arithmetic number, because the mean of its divisors is an integer number (40986802).

Almost surely, 2^81973603 is an apocalyptic number.

81973603 is a deficient number, since it is larger than the sum of its proper divisors (1).

81973603 is an equidigital number, since it uses as much as digits as its factorization.

81973603 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27216, while the sum is 37.

The square root of 81973603 is about 9053.9274903215. The cubic root of 81973603 is about 434.4015251680.

The spelling of 81973603 in words is "eighty-one million, nine hundred seventy-three thousand, six hundred three".