81770850 has 192 divisors, whose sum is σ = 273196800. Its totient is φ = 17556480.

The previous prime is 81770837. The next prime is 81770881. The reversal of 81770850 is 5807718.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 160396 + ... + 160904.

It is an arithmetic number, because the mean of its divisors is an integer number (1422900).

Almost surely, 2^81770850 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81770850, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (136598400).

81770850 is an abundant number, since it is smaller than the sum of its proper divisors (191425950).

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

81770850 is a wasteful number, since it uses less digits than its factorization.

81770850 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 554 (or 543 counting only the distinct ones).

The product of its (nonzero) digits is 15680, while the sum is 36.

The square root of 81770850 is about 9042.7235941391. The cubic root of 81770850 is about 434.0430808035.

The spelling of 81770850 in words is "eighty-one million, seven hundred seventy thousand, eight hundred fifty".