2172240 has 120 divisors (see below), whose sum is σ = 8356608. Its totient is φ = 495360.

The previous prime is 2172239. The next prime is 2172241. The reversal of 2172240 is 422712.

It is an interprime number because it is at equal distance from previous prime (2172239) and next prime (2172241).

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2172241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4825 + ... + 5255.

2^2172240 is an apocalyptic number.

2172240 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 2172240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4178304).

2172240 is an abundant number, since it is smaller than the sum of its proper divisors (6184368).

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

2172240 is a wasteful number, since it uses less digits than its factorization.

2172240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 457 (or 448 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 18.

The square root of 2172240 is about 1473.8520957002. The cubic root of 2172240 is about 129.5097909047.

Adding to 2172240 its reverse (422712), we get a palindrome (2594952).

The spelling of 2172240 in words is "two million, one hundred seventy-two thousand, two hundred forty".