81216760 has 16 divisors (see below), whose sum is σ = 182737800. Its totient is φ = 32486688.

The previous prime is 81216757. The next prime is 81216761. The reversal of 81216760 is 6761218.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81216761) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1015170 + ... + 1015249.

Almost surely, 2^81216760 is an apocalyptic number.

It is an amenable number.

81216760 is an abundant number, since it is smaller than the sum of its proper divisors (101521040).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81216760 is a wasteful number, since it uses less digits than its factorization.

81216760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2030430 (or 2030426 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 81216760 is about 9012.0341765885. The cubic root of 81216760 is about 433.0604804339.

Adding to 81216760 its reverse (6761218), we get a palindrome (87977978).

The spelling of 81216760 in words is "eighty-one million, two hundred sixteen thousand, seven hundred sixty".