81493120903 has 2 divisors, whose sum is σ = 81493120904. Its totient is φ = 81493120902.

The previous prime is 81493120889. The next prime is 81493120927. The reversal of 81493120903 is 30902139418.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81493120903 - 2⁵ = 81493120871 is a prime.

It is a super-2 number, since 2×81493120903² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81493120003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40746560451 + 40746560452.

It is an arithmetic number, because the mean of its divisors is an integer number (40746560452).

Almost surely, 2^81493120903 is an apocalyptic number.

81493120903 is a deficient number, since it is larger than the sum of its proper divisors (1).

81493120903 is an equidigital number, since it uses as much as digits as its factorization.

81493120903 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 46656, while the sum is 40.

The spelling of 81493120903 in words is "eighty-one billion, four hundred ninety-three million, one hundred twenty thousand, nine hundred three".