81071697 has 8 divisors (see below), whose sum is σ = 123537856. Its totient is φ = 46326672.

The previous prime is 81071687. The next prime is 81071701. The reversal of 81071697 is 79617018.

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

It is not a de Polignac number, because 81071697 - 2⁴ = 81071681 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81071647) 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, 1930258 + ... + 1930299.

It is an arithmetic number, because the mean of its divisors is an integer number (15442232).

Almost surely, 2^81071697 is an apocalyptic number.

It is an amenable number.

81071697 is a deficient number, since it is larger than the sum of its proper divisors (42466159).

81071697 is a wasteful number, since it uses less digits than its factorization.

81071697 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3860567.

The product of its (nonzero) digits is 21168, while the sum is 39.

The square root of 81071697 is about 9003.9822856334. The cubic root of 81071697 is about 432.8024938982.

The spelling of 81071697 in words is "eighty-one million, seventy-one thousand, six hundred ninety-seven".