81996035249 has 2 divisors, whose sum is σ = 81996035250. Its totient is φ = 81996035248.

The previous prime is 81996035167. The next prime is 81996035267. The reversal of 81996035249 is 94253069918.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 80198275249 + 1797760000 = 283193^2 + 42400^2 .

It is a cyclic number.

It is not a de Polignac number, because 81996035249 - 2⁸ = 81996034993 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81996035194 and 81996035203.

It is not a weakly prime, because it can be changed into another prime (81996038249) 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, 40998017624 + 40998017625.

It is an arithmetic number, because the mean of its divisors is an integer number (40998017625).

Almost surely, 2^81996035249 is an apocalyptic number.

It is an amenable number.

81996035249 is a deficient number, since it is larger than the sum of its proper divisors (1).

81996035249 is an equidigital number, since it uses as much as digits as its factorization.

81996035249 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4199040, while the sum is 56.

The spelling of 81996035249 in words is "eighty-one billion, nine hundred ninety-six million, thirty-five thousand, two hundred forty-nine".