6665406 has 24 divisors (see below), whose sum is σ = 14654472. Its totient is φ = 2019600.

The previous prime is 6665383. The next prime is 6665413. The reversal of 6665406 is 6045666.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is an Ulam number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3865 + ... + 5316.

It is an arithmetic number, because the mean of its divisors is an integer number (610603).

Almost surely, 2^6665406 is an apocalyptic number.

6665406 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

6665406 is an abundant number, since it is smaller than the sum of its proper divisors (7989066).

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

6665406 is a wasteful number, since it uses less digits than its factorization.

6665406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9208 (or 9197 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 33.

The square root of 6665406 is about 2581.7447588792. The cubic root of 6665406 is about 188.1953417008.

The spelling of 6665406 in words is "six million, six hundred sixty-five thousand, four hundred six".