6665538 has 32 divisors (see below), whose sum is σ = 15178752. Its totient is φ = 1931600.

The previous prime is 6665537. The next prime is 6665539. The reversal of 6665538 is 8355666.

It is an interprime number because it is at equal distance from previous prime (6665537) and next prime (6665539).

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 6665496 and 6665505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6665537) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 678 + ... + 3713.

It is an arithmetic number, because the mean of its divisors is an integer number (474336).

Almost surely, 2^6665538 is an apocalyptic number.

6665538 is an abundant number, since it is smaller than the sum of its proper divisors (8513214).

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

6665538 is a wasteful number, since it uses less digits than its factorization.

6665538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4430.

The product of its digits is 129600, while the sum is 39.

The square root of 6665538 is about 2581.7703228599. The cubic root of 6665538 is about 188.1965840168.

The spelling of 6665538 in words is "six million, six hundred sixty-five thousand, five hundred thirty-eight".