6623681 has 4 divisors (see below), whose sum is σ = 6689364. Its totient is φ = 6558000.

The previous prime is 6623611. The next prime is 6623707. The reversal of 6623681 is 1863266.

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 3182656 + 3441025 = 1784^2 + 1855^2 .

It is a cyclic number.

It is not a de Polignac number, because 6623681 - 2¹⁴ = 6607297 is a prime.

It is a super-2 number, since 2×6623681² = 87746299979522, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (6623611) 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, 32690 + ... + 32891.

It is an arithmetic number, because the mean of its divisors is an integer number (1672341).

Almost surely, 2^6623681 is an apocalyptic number.

It is an amenable number.

6623681 is a deficient number, since it is larger than the sum of its proper divisors (65683).

6623681 is a wasteful number, since it uses less digits than its factorization.

6623681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65682.

The product of its digits is 10368, while the sum is 32.

The square root of 6623681 is about 2573.6512972817. The cubic root of 6623681 is about 187.8018226299.

The spelling of 6623681 in words is "six million, six hundred twenty-three thousand, six hundred eighty-one".