81726336 has 96 divisors (see below), whose sum is σ = 239236920. Its totient is φ = 26772480.

The previous prime is 81726331. The next prime is 81726341. The reversal of 81726336 is 63362718.

It is a happy number.

81726336 is a `hidden beast` number, since 8 + 17 + 2 + 633 + 6 = 666.

It is an interprime number because it is at equal distance from previous prime (81726331) and next prime (81726341).

It is a tau number, because it is divible by the number of its divisors (96).

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 81726336.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81726331) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 69691 + ... + 70853.

Almost surely, 2^81726336 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 81726336, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (119618460).

81726336 is an abundant number, since it is smaller than the sum of its proper divisors (157510584).

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

81726336 is a wasteful number, since it uses less digits than its factorization.

81726336 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1244 (or 1229 counting only the distinct ones).

The product of its digits is 36288, while the sum is 36.

The square root of 81726336 is about 9040.2619431076. The cubic root of 81726336 is about 433.9643057848.

The spelling of 81726336 in words is "eighty-one million, seven hundred twenty-six thousand, three hundred thirty-six".