1985660 has 24 divisors (see below), whose sum is σ = 4215456. Its totient is φ = 785600.

The previous prime is 1985639. The next prime is 1985663. The reversal of 1985660 is 665891.

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 1985660.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1985663) 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, 1529 + ... + 2511.

It is an arithmetic number, because the mean of its divisors is an integer number (175644).

2^1985660 is an apocalyptic number.

1985660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1985660 is an abundant number, since it is smaller than the sum of its proper divisors (2229796).

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

1985660 is a wasteful number, since it uses less digits than its factorization.

1985660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1093 (or 1091 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 35.

The square root of 1985660 is about 1409.1344861297. The cubic root of 1985660 is about 125.6902612986.

The spelling of 1985660 in words is "one million, nine hundred eighty-five thousand, six hundred sixty".