2166388 has 24 divisors (see below), whose sum is σ = 4424000. Its totient is φ = 927864.

The previous prime is 2166319. The next prime is 2166403. The reversal of 2166388 is 8836612.

It is a d-powerful number, because it can be written as 2²¹ + 1 + 6³ + 6⁴ + 3⁷ + 8⁵ + 8⁵ .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 583 + ... + 2161.

2^2166388 is an apocalyptic number.

2166388 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2166388, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2212000).

2166388 is an abundant number, since it is smaller than the sum of its proper divisors (2257612).

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

2166388 is a wasteful number, since it uses less digits than its factorization.

2166388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1604 (or 1588 counting only the distinct ones).

The product of its digits is 13824, while the sum is 34.

The square root of 2166388 is about 1471.8654829841. The cubic root of 2166388 is about 129.3933868085.

The spelling of 2166388 in words is "two million, one hundred sixty-six thousand, three hundred eighty-eight".