81256236 has 24 divisors (see below), whose sum is σ = 199577280. Its totient is φ = 25659792.

The previous prime is 81256229. The next prime is 81256247. The reversal of 81256236 is 63265218.

It is a junction number, because it is equal to n+sod(n) for n = 81256197 and 81256206.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 177966 + ... + 178421.

It is an arithmetic number, because the mean of its divisors is an integer number (8315720).

Almost surely, 2^81256236 is an apocalyptic number.

It is an amenable number.

81256236 is an abundant number, since it is smaller than the sum of its proper divisors (118321044).

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

81256236 is a wasteful number, since it uses less digits than its factorization.

81256236 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 356413 (or 356411 counting only the distinct ones).

The product of its digits is 17280, while the sum is 33.

The square root of 81256236 is about 9014.2240930654. The cubic root of 81256236 is about 433.1306331399.

The spelling of 81256236 in words is "eighty-one million, two hundred fifty-six thousand, two hundred thirty-six".