81168912 has 320 divisors, whose sum is σ = 285696000. Its totient is φ = 21772800.

The previous prime is 81168887. The next prime is 81168929. The reversal of 81168912 is 21986118.

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 an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2618337 + ... + 2618367.

It is an arithmetic number, because the mean of its divisors is an integer number (892800).

Almost surely, 2^81168912 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 81168912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (142848000).

81168912 is an abundant number, since it is smaller than the sum of its proper divisors (204527088).

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

81168912 is a wasteful number, since it uses less digits than its factorization.

81168912 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107 (or 95 counting only the distinct ones).

The product of its digits is 6912, while the sum is 36.

The square root of 81168912 is about 9009.3791129023. The cubic root of 81168912 is about 432.9754193849.

The spelling of 81168912 in words is "eighty-one million, one hundred sixty-eight thousand, nine hundred twelve".