1881780 has 48 divisors (see below), whose sum is σ = 5349120. Its totient is φ = 494208.

The previous prime is 1881769. The next prime is 1881787. The reversal of 1881780 is 871881.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1881787) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4542 + ... + 4938.

It is an arithmetic number, because the mean of its divisors is an integer number (111440).

2^1881780 is an apocalyptic number.

1881780 is a gapful number since it is divisible by the number (10) 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 1881780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2674560).

1881780 is an abundant number, since it is smaller than the sum of its proper divisors (3467340).

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

1881780 is a wasteful number, since it uses less digits than its factorization.

1881780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 488 (or 486 counting only the distinct ones).

The product of its (nonzero) digits is 3584, while the sum is 33.

The square root of 1881780 is about 1371.7798657219. The cubic root of 1881780 is about 123.4590553074.

The spelling of 1881780 in words is "one million, eight hundred eighty-one thousand, seven hundred eighty".