81403767 has 6 divisors (see below), whose sum is σ = 117583232. Its totient is φ = 54269172.

The previous prime is 81403759. The next prime is 81403787. The reversal of 81403767 is 76730418.

It is not a de Polignac number, because 81403767 - 2³ = 81403759 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81403747) 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 in 5 ways as a sum of consecutive naturals, for example, 4522423 + ... + 4522440.

Almost surely, 2^81403767 is an apocalyptic number.

81403767 is a deficient number, since it is larger than the sum of its proper divisors (36179465).

81403767 is a wasteful number, since it uses less digits than its factorization.

81403767 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9044869 (or 9044866 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 36.

The square root of 81403767 is about 9022.4036154453. The cubic root of 81403767 is about 433.3926091825.

The spelling of 81403767 in words is "eighty-one million, four hundred three thousand, seven hundred sixty-seven".