81167256 has 24 divisors (see below), whose sum is σ = 219828180. Its totient is φ = 27055728.

The previous prime is 81167237. The next prime is 81167257. The reversal of 81167256 is 65276118.

It is a tau number, because it is divible by the number of its divisors (24).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 81167256.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81167257) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 563590 + ... + 563733.

Almost surely, 2^81167256 is an apocalyptic number.

It is an amenable number.

81167256 is an abundant number, since it is smaller than the sum of its proper divisors (138660924).

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

81167256 is a wasteful number, since it uses less digits than its factorization.

81167256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1127335 (or 1127328 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 81167256 is about 9009.2872082091. The cubic root of 81167256 is about 432.9724748578.

The spelling of 81167256 in words is "eighty-one million, one hundred sixty-seven thousand, two hundred fifty-six".