81759800 has 96 divisors (see below), whose sum is σ = 203893200. Its totient is φ = 30382080.

The previous prime is 81759773. The next prime is 81759827. The reversal of 81759800 is 895718.

It is an interprime number because it is at equal distance from previous prime (81759773) and next prime (81759827).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 472514 + ... + 472686.

Almost surely, 2^81759800 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 81759800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (101946600).

81759800 is an abundant number, since it is smaller than the sum of its proper divisors (122133400).

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

81759800 is a wasteful number, since it uses less digits than its factorization.

81759800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 345 (or 336 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 38.

The square root of 81759800 is about 9042.1125850102. The cubic root of 81759800 is about 434.0235286359.

The spelling of 81759800 in words is "eighty-one million, seven hundred fifty-nine thousand, eight hundred".