81706080 has 288 divisors, whose sum is σ = 297077760. Its totient is φ = 18800640.

The previous prime is 81706067. The next prime is 81706109. The reversal of 81706080 is 8060718.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2635665 + ... + 2635695.

It is an arithmetic number, because the mean of its divisors is an integer number (1031520).

Almost surely, 2^81706080 is an apocalyptic number.

81706080 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81706080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (148538880).

81706080 is an abundant number, since it is smaller than the sum of its proper divisors (215371680).

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

81706080 is a wasteful number, since it uses less digits than its factorization.

81706080 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102 (or 77 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 30.

The square root of 81706080 is about 9039.1415521608. The cubic root of 81706080 is about 433.9284499120.

Adding to 81706080 its reverse (8060718), we get a palindrome (89766798).

The spelling of 81706080 in words is "eighty-one million, seven hundred six thousand, eighty".