2143890 has 96 divisors (see below), whose sum is σ = 6604416. Its totient is φ = 472320.

The previous prime is 2143877. The next prime is 2143901. The reversal of 2143890 is 983412.

It is an Ulam number.

It is an alternating number because its digits alternate between even and odd.

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 47 ways as a sum of consecutive naturals, for example, 25789 + ... + 25871.

It is an arithmetic number, because the mean of its divisors is an integer number (68796).

2^2143890 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2143890, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3302208).

2143890 is an abundant number, since it is smaller than the sum of its proper divisors (4460526).

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

2143890 is a wasteful number, since it uses less digits than its factorization.

2143890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144 (or 141 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 2143890 is about 1464.2028547985. The cubic root of 2143890 is about 128.9439092725.

It can be divided in two parts, 21438 and 90, that added together give a triangular number (21528 = T₂₀₇).

The spelling of 2143890 in words is "two million, one hundred forty-three thousand, eight hundred ninety".