81701120 has 144 divisors (see below), whose sum is σ = 211921920. Its totient is φ = 30105600.

The previous prime is 81701119. The next prime is 81701171. The reversal of 81701120 is 2110718.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 81701092 and 81701101.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1150685 + ... + 1150755.

It is an arithmetic number, because the mean of its divisors is an integer number (1471680).

Almost surely, 2^81701120 is an apocalyptic number.

81701120 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 81701120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (105960960).

81701120 is an abundant number, since it is smaller than the sum of its proper divisors (130220800).

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

81701120 is a wasteful number, since it uses less digits than its factorization.

81701120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152 (or 138 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 20.

The square root of 81701120 is about 9038.8671856599. The cubic root of 81701120 is about 433.9196691348.

Adding to 81701120 its reverse (2110718), we get a palindrome (83811838).

The spelling of 81701120 in words is "eighty-one million, seven hundred one thousand, one hundred twenty".