2166406 has 8 divisors (see below), whose sum is σ = 3545064. Its totient is φ = 984720.

The previous prime is 2166403. The next prime is 2166407. The reversal of 2166406 is 6046612.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2166403) 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, 49215 + ... + 49258.

It is an arithmetic number, because the mean of its divisors is an integer number (443133).

2^2166406 is an apocalyptic number.

2166406 is a deficient number, since it is larger than the sum of its proper divisors (1378658).

2166406 is a wasteful number, since it uses less digits than its factorization.

2166406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98486.

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 2166406 is about 1471.8715976606. The cubic root of 2166406 is about 129.3937451738.

The spelling of 2166406 in words is "two million, one hundred sixty-six thousand, four hundred six".