2166840 has 96 divisors (see below), whose sum is σ = 7600320. Its totient is φ = 532224.

The previous prime is 2166833. The next prime is 2166877. The reversal of 2166840 is 486612.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4449 + ... + 4911.

It is an arithmetic number, because the mean of its divisors is an integer number (79170).

2^2166840 is an apocalyptic number.

2166840 is a gapful number since it is divisible by the number (20) 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 2166840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3800160).

2166840 is an abundant number, since it is smaller than the sum of its proper divisors (5433480).

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

2166840 is a wasteful number, since it uses less digits than its factorization.

2166840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 493 (or 486 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 2166840 is about 1472.0190216162. The cubic root of 2166840 is about 129.4023851572.

It can be divided in two parts, 216 and 6840, that added together give a square (7056 = 84²).

The spelling of 2166840 in words is "two million, one hundred sixty-six thousand, eight hundred forty".