8320661 has 4 divisors (see below), whose sum is σ = 8371872. Its totient is φ = 8269452.

The previous prime is 8320657. The next prime is 8320681. The reversal of 8320661 is 1660238.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 8320661 - 2² = 8320657 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 8320661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8320601) 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, 25361 + ... + 25686.

It is an arithmetic number, because the mean of its divisors is an integer number (2092968).

Almost surely, 2^8320661 is an apocalyptic number.

It is an amenable number.

8320661 is a deficient number, since it is larger than the sum of its proper divisors (51211).

8320661 is a wasteful number, since it uses less digits than its factorization.

8320661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51210.

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 8320661 is about 2884.5555983548. Note that the first 4 decimals coincide. The cubic root of 8320661 is about 202.6372467947.

Adding to 8320661 its reverse (1660238), we get a palindrome (9980899).

The spelling of 8320661 in words is "eight million, three hundred twenty thousand, six hundred sixty-one".