7866641 has 4 divisors (see below), whose sum is σ = 7874484. Its totient is φ = 7858800.

The previous prime is 7866637. The next prime is 7866643. The reversal of 7866641 is 1466687.

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 7311616 + 555025 = 2704^2 + 745^2 .

It is a cyclic number.

It is not a de Polignac number, because 7866641 - 2² = 7866637 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 7866595 and 7866604.

It is not an unprimeable number, because it can be changed into a prime (7866643) 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, 2150 + ... + 4511.

It is an arithmetic number, because the mean of its divisors is an integer number (1968621).

Almost surely, 2^7866641 is an apocalyptic number.

It is an amenable number.

7866641 is a deficient number, since it is larger than the sum of its proper divisors (7843).

7866641 is a wasteful number, since it uses less digits than its factorization.

7866641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7842.

The product of its digits is 48384, while the sum is 38.

The square root of 7866641 is about 2804.7532868329. The cubic root of 7866641 is about 198.8824419514.

The spelling of 7866641 in words is "seven million, eight hundred sixty-six thousand, six hundred forty-one".