1985790 has 32 divisors (see below), whose sum is σ = 4897440. Its totient is φ = 514944.

The previous prime is 1985779. The next prime is 1985791. The reversal of 1985790 is 975891.

It is a happy number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1985791) 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, 216 + ... + 2004.

It is an arithmetic number, because the mean of its divisors is an integer number (153045).

2^1985790 is an apocalyptic number.

1985790 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1985790, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2448720).

1985790 is an abundant number, since it is smaller than the sum of its proper divisors (2911650).

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

1985790 is a wasteful number, since it uses less digits than its factorization.

1985790 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1836.

The product of its (nonzero) digits is 22680, while the sum is 39.

The square root of 1985790 is about 1409.1806129805. The cubic root of 1985790 is about 125.6930041947.

It can be divided in two parts, 1985 and 790, that added together give a triangular number (2775 = T₇₄).

The spelling of 1985790 in words is "one million, nine hundred eighty-five thousand, seven hundred ninety".