81293288 has 16 divisors (see below), whose sum is σ = 152569860. Its totient is φ = 40608000.

The previous prime is 81293287. The next prime is 81293323. The reversal of 81293288 is 88239218.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 78464164 + 2829124 = 8858^2 + 1682^2 .

It is not an unprimeable number, because it can be changed into a prime (81293281) 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, 5378 + ... + 13838.

Almost surely, 2^81293288 is an apocalyptic number.

It is an amenable number.

81293288 is a deficient number, since it is larger than the sum of its proper divisors (71276572).

81293288 is a wasteful number, since it uses less digits than its factorization.

81293288 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9668 (or 9664 counting only the distinct ones).

The product of its digits is 55296, while the sum is 41.

The square root of 81293288 is about 9016.2790551313. The cubic root of 81293288 is about 433.1964574932.

The spelling of 81293288 in words is "eighty-one million, two hundred ninety-three thousand, two hundred eighty-eight".