81536877 has 6 divisors (see below), whose sum is σ = 117775502. Its totient is φ = 54357912.

The previous prime is 81536857. The next prime is 81536911. The reversal of 81536877 is 77863518.

It can be written as a sum of positive squares in only one way, i.e., 47734281 + 33802596 = 6909^2 + 5814^2 .

It is not a de Polignac number, because 81536877 - 2⁸ = 81536621 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 (81536837) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4529818 + ... + 4529835.

Almost surely, 2^81536877 is an apocalyptic number.

It is an amenable number.

81536877 is a deficient number, since it is larger than the sum of its proper divisors (36238625).

81536877 is a wasteful number, since it uses less digits than its factorization.

81536877 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9059659 (or 9059656 counting only the distinct ones).

The product of its digits is 282240, while the sum is 45.

The square root of 81536877 is about 9029.7772397773. Note that the first 3 decimals coincide. The cubic root of 81536877 is about 433.6287058519.

The spelling of 81536877 in words is "eighty-one million, five hundred thirty-six thousand, eight hundred seventy-seven".