8643961 has 4 divisors (see below), whose sum is σ = 8733172. Its totient is φ = 8554752.

The previous prime is 8643959. The next prime is 8643991. The reversal of 8643961 is 1693468.

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 3825936 + 4818025 = 1956^2 + 2195^2 .

It is a cyclic number.

It is not a de Polignac number, because 8643961 - 2¹ = 8643959 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 8643961.

It is not an unprimeable number, because it can be changed into a prime (8643941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 44460 + ... + 44653.

It is an arithmetic number, because the mean of its divisors is an integer number (2183293).

Almost surely, 2^8643961 is an apocalyptic number.

It is an amenable number.

8643961 is a deficient number, since it is larger than the sum of its proper divisors (89211).

8643961 is an equidigital number, since it uses as much as digits as its factorization.

8643961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89210.

The product of its digits is 31104, while the sum is 37.

The square root of 8643961 is about 2940.0613939168. The cubic root of 8643961 is about 205.2284662861.

It can be divided in two parts, 8643 and 961, that added together give a square (9604 = 98²).

The spelling of 8643961 in words is "eight million, six hundred forty-three thousand, nine hundred sixty-one".