6866538 has 64 divisors (see below), whose sum is σ = 17003520. Its totient is φ = 1804032.

The previous prime is 6866513. The next prime is 6866549. The reversal of 6866538 is 8356686.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is an Ulam number.

It is a Curzon number.

It is a nialpdrome in base 14.

It is a self number, because there is not a number n which added to its sum of digits gives 6866538.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 42045 + ... + 42207.

It is an arithmetic number, because the mean of its divisors is an integer number (265680).

Almost surely, 2^6866538 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6866538, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8501760).

6866538 is an abundant number, since it is smaller than the sum of its proper divisors (10136982).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6866538 is a wasteful number, since it uses less digits than its factorization.

6866538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 251.

The product of its digits is 207360, while the sum is 42.

The square root of 6866538 is about 2620.4079835018. The cubic root of 6866538 is about 190.0695774726.

The spelling of 6866538 in words is "six million, eight hundred sixty-six thousand, five hundred thirty-eight".