8721697 has 4 divisors (see below), whose sum is σ = 9234756. Its totient is φ = 8208640.

The previous prime is 8721673. The next prime is 8721701. The reversal of 8721697 is 7961278.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4124961 + 4596736 = 2031^2 + 2144^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8721697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8721607) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 256504 + ... + 256537.

It is an arithmetic number, because the mean of its divisors is an integer number (2308689).

Almost surely, 2^8721697 is an apocalyptic number.

It is an amenable number.

8721697 is a deficient number, since it is larger than the sum of its proper divisors (513059).

8721697 is a wasteful number, since it uses less digits than its factorization.

8721697 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 513058.

The product of its digits is 42336, while the sum is 40.

The square root of 8721697 is about 2953.2519364253. The cubic root of 8721697 is about 205.8418445489.

The spelling of 8721697 in words is "eight million, seven hundred twenty-one thousand, six hundred ninety-seven".