8239661 has 4 divisors (see below), whose sum is σ = 8245500. Its totient is φ = 8233824.

The previous prime is 8239639. The next prime is 8239667. The reversal of 8239661 is 1669328.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 649636 + 7590025 = 806^2 + 2755^2 .

It is a cyclic number.

It is not a de Polignac number, because 8239661 - 2¹⁸ = 7977517 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 (8239667) 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, 665 + ... + 4113.

It is an arithmetic number, because the mean of its divisors is an integer number (2061375).

Almost surely, 2^8239661 is an apocalyptic number.

It is an amenable number.

8239661 is a deficient number, since it is larger than the sum of its proper divisors (5839).

8239661 is a wasteful number, since it uses less digits than its factorization.

8239661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5838.

The product of its digits is 15552, while the sum is 35.

The square root of 8239661 is about 2870.4809701512. The cubic root of 8239661 is about 201.9775568962.

The spelling of 8239661 in words is "eight million, two hundred thirty-nine thousand, six hundred sixty-one".