81355008 has 144 divisors (see below), whose sum is σ = 254764160. Its totient is φ = 22560768.

The previous prime is 81355007. The next prime is 81355019. The reversal of 81355008 is 80055318.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (81355007) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 198708 + ... + 199116.

Almost surely, 2^81355008 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 81355008, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (127382080).

81355008 is an abundant number, since it is smaller than the sum of its proper divisors (173409152).

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

81355008 is a wasteful number, since it uses less digits than its factorization.

81355008 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 472 (or 458 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 30.

The square root of 81355008 is about 9019.7011036952. The cubic root of 81355008 is about 433.3060611370.

The spelling of 81355008 in words is "eighty-one million, three hundred fifty-five thousand, eight".