81516735 has 48 divisors (see below), whose sum is σ = 146469024. Its totient is φ = 41907456.

The previous prime is 81516727. The next prime is 81516739. The reversal of 81516735 is 53761518.

It is not a de Polignac number, because 81516735 - 2³ = 81516727 is a prime.

Its product of digits (25200) is a multiple of the sum of its prime factors (504).

It is a self number, because there is not a number n which added to its sum of digits gives 81516735.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81516739) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 287904 + ... + 288186.

It is an arithmetic number, because the mean of its divisors is an integer number (3051438).

Almost surely, 2^81516735 is an apocalyptic number.

81516735 is a deficient number, since it is larger than the sum of its proper divisors (64952289).

81516735 is a wasteful number, since it uses less digits than its factorization.

81516735 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 504 (or 501 counting only the distinct ones).

The product of its digits is 25200, while the sum is 36.

The square root of 81516735 is about 9028.6618609847. The cubic root of 81516735 is about 433.5929965753.

The spelling of 81516735 in words is "eighty-one million, five hundred sixteen thousand, seven hundred thirty-five".