2161920 has 72 divisors (see below), whose sum is σ = 6916896. Its totient is φ = 575488.

The previous prime is 2161919. The next prime is 2161927. The reversal of 2161920 is 291612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2161927) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3559 + ... + 4121.

It is an arithmetic number, because the mean of its divisors is an integer number (96068).

2^2161920 is an apocalyptic number.

2161920 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 2161920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3458448).

2161920 is an abundant number, since it is smaller than the sum of its proper divisors (4754976).

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

2161920 is an equidigital number, since it uses as much as digits as its factorization.

2161920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 587 (or 573 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 21.

The square root of 2161920 is about 1470.3468978442. The cubic root of 2161920 is about 129.3043711202.

It can be divided in two parts, 2161 and 920, that added together give a triangular number (3081 = T₇₈).

The spelling of 2161920 in words is "two million, one hundred sixty-one thousand, nine hundred twenty".