1801660 has 48 divisors (see below), whose sum is σ = 4584384. Its totient is φ = 580608.

The previous prime is 1801619. The next prime is 1801669. The reversal of 1801660 is 661081.

1801660 = 8² + 9² + ... + 175².

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1801669) 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, 2002 + ... + 2758.

It is an arithmetic number, because the mean of its divisors is an integer number (95508).

2^1801660 is an apocalyptic number.

1801660 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 1801660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2292192).

1801660 is an abundant number, since it is smaller than the sum of its proper divisors (2782724).

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

1801660 is a wasteful number, since it uses less digits than its factorization.

1801660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 790 (or 788 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 22.

The square root of 1801660 is about 1342.2592894072. The cubic root of 1801660 is about 121.6814227010.

The spelling of 1801660 in words is "one million, eight hundred one thousand, six hundred sixty".