2011780 has 48 divisors (see below), whose sum is σ = 4593456. Its totient is φ = 737280.

The previous prime is 2011769. The next prime is 2011799. The reversal of 2011780 is 871102.

It can be written as a sum of positive squares in 8 ways, for example, as 123904 + 1887876 = 352^2 + 1374^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20692 + ... + 20788.

It is an arithmetic number, because the mean of its divisors is an integer number (95697).

2^2011780 is an apocalyptic number.

2011780 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 2011780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2296728).

2011780 is an abundant number, since it is smaller than the sum of its proper divisors (2581676).

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

2011780 is a wasteful number, since it uses less digits than its factorization.

2011780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 184 (or 182 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 19.

The square root of 2011780 is about 1418.3723065542. The cubic root of 2011780 is about 126.2389854130.

Adding to 2011780 its reverse (871102), we get a palindrome (2882882).

The spelling of 2011780 in words is "two million, eleven thousand, seven hundred eighty".