81337288 has 8 divisors (see below), whose sum is σ = 152507430. Its totient is φ = 40668640.

The previous prime is 81337283. The next prime is 81337297. The reversal of 81337288 is 88273318.

It can be written as a sum of positive squares in only one way, i.e., 46267204 + 35070084 = 6802^2 + 5922^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a self number, because there is not a number n which added to its sum of digits gives 81337288.

It is not an unprimeable number, because it can be changed into a prime (81337283) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5083573 + ... + 5083588.

Almost surely, 2^81337288 is an apocalyptic number.

It is an amenable number.

81337288 is a deficient number, since it is larger than the sum of its proper divisors (71170142).

81337288 is a wasteful number, since it uses less digits than its factorization.

81337288 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10167167 (or 10167163 counting only the distinct ones).

The product of its digits is 64512, while the sum is 40.

The square root of 81337288 is about 9018.7187560096. The cubic root of 81337288 is about 433.2745992716.

The spelling of 81337288 in words is "eighty-one million, three hundred thirty-seven thousand, two hundred eighty-eight".