81326288 has 20 divisors (see below), whose sum is σ = 161414148. Its totient is φ = 39671040.

The previous prime is 81326281. The next prime is 81326291. The reversal of 81326288 is 88262318.

It can be written as a sum of positive squares in 2 ways, for example, as 26091664 + 55234624 = 5108^2 + 7432^2 .

It is a super-2 number, since 2×81326288² = 13227930239717888, which contains 22 as substring.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81326281) 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, 61331 + ... + 62642.

Almost surely, 2^81326288 is an apocalyptic number.

It is an amenable number.

81326288 is a deficient number, since it is larger than the sum of its proper divisors (80087860).

81326288 is a wasteful number, since it uses less digits than its factorization.

81326288 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 124022 (or 124016 counting only the distinct ones).

The product of its digits is 36864, while the sum is 38.

The square root of 81326288 is about 9018.1088926670. The cubic root of 81326288 is about 433.2550664695.

The spelling of 81326288 in words is "eighty-one million, three hundred twenty-six thousand, two hundred eighty-eight".