81788850 has 288 divisors, whose sum is σ = 272982528. Its totient is φ = 17280000.

The previous prime is 81788831. The next prime is 81788867. The reversal of 81788850 is 5888718.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a junction number, because it is equal to n+sod(n) for n = 81788796 and 81788805.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 1994830 + ... + 1994870.

It is an arithmetic number, because the mean of its divisors is an integer number (947856).

Almost surely, 2^81788850 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81788850, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (136491264).

81788850 is an abundant number, since it is smaller than the sum of its proper divisors (191193678).

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

81788850 is a wasteful number, since it uses less digits than its factorization.

81788850 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114 (or 106 counting only the distinct ones).

The product of its (nonzero) digits is 143360, while the sum is 45.

The square root of 81788850 is about 9043.7188147355. The cubic root of 81788850 is about 434.0749267170.

The spelling of 81788850 in words is "eighty-one million, seven hundred eighty-eight thousand, eight hundred fifty".