81708901 has 8 divisors (see below), whose sum is σ = 86307584. Its totient is φ = 77232960.

The previous prime is 81708883. The next prime is 81708917. The reversal of 81708901 is 10980718.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81708901 - 2⁷ = 81708773 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81708931) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29316 + ... + 31981.

It is an arithmetic number, because the mean of its divisors is an integer number (10788448).

Almost surely, 2^81708901 is an apocalyptic number.

It is an amenable number.

81708901 is a deficient number, since it is larger than the sum of its proper divisors (4598683).

81708901 is a wasteful number, since it uses less digits than its factorization.

81708901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61371.

The product of its (nonzero) digits is 4032, while the sum is 34.

The square root of 81708901 is about 9039.2975943931. The cubic root of 81708901 is about 433.9334438206.

It can be divided in two parts, 8170 and 8901, that added together give a palindrome (17071).

The spelling of 81708901 in words is "eighty-one million, seven hundred eight thousand, nine hundred one".