81710900 has 36 divisors (see below), whose sum is σ = 179324460. Its totient is φ = 32313600.

The previous prime is 81710897. The next prime is 81710917. The reversal of 81710900 is 901718.

It can be written as a sum of positive squares in 6 ways, for example, as 4376464 + 77334436 = 2092^2 + 8794^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 81710900.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4310 + ... + 13490.

It is an arithmetic number, because the mean of its divisors is an integer number (4981235).

Almost surely, 2^81710900 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 81710900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89662230).

81710900 is an abundant number, since it is smaller than the sum of its proper divisors (97613560).

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

81710900 is a wasteful number, since it uses less digits than its factorization.

81710900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9284 (or 9277 counting only the distinct ones).

The product of its (nonzero) digits is 504, while the sum is 26.

The square root of 81710900 is about 9039.4081664675. The cubic root of 81710900 is about 433.9369825043.

The spelling of 81710900 in words is "eighty-one million, seven hundred ten thousand, nine hundred".