81296136 has 192 divisors, whose sum is σ = 251596800. Its totient is φ = 24494400.

The previous prime is 81296123. The next prime is 81296143. The reversal of 81296136 is 63169218.

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

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 81296136.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1144981 + ... + 1145051.

It is an arithmetic number, because the mean of its divisors is an integer number (1310400).

Almost surely, 2^81296136 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81296136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (125798400).

81296136 is an abundant number, since it is smaller than the sum of its proper divisors (170300664).

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

81296136 is a wasteful number, since it uses less digits than its factorization.

81296136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142 (or 126 counting only the distinct ones).

The product of its digits is 15552, while the sum is 36.

The square root of 81296136 is about 9016.4369902972. The cubic root of 81296136 is about 433.2015162507.

The spelling of 81296136 in words is "eighty-one million, two hundred ninety-six thousand, one hundred thirty-six".