81013608 has 160 divisors (see below), whose sum is σ = 250034400. Its totient is φ = 24354432.

The previous prime is 81013607. The next prime is 81013643. The reversal of 81013608 is 80631018.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (81013601) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 496935 + ... + 497097.

It is an arithmetic number, because the mean of its divisors is an integer number (1562715).

Almost surely, 2^81013608 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 81013608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (125017200).

81013608 is an abundant number, since it is smaller than the sum of its proper divisors (169020792).

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

81013608 is a wasteful number, since it uses less digits than its factorization.

81013608 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 253 (or 240 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 81013608 is about 9000.7559682507. The cubic root of 81013608 is about 432.6990995283.

The spelling of 81013608 in words is "eighty-one million, thirteen thousand, six hundred eight".