133785 has 16 divisors (see below), whose sum is σ = 238080. Its totient is φ = 71280.

The previous prime is 133781. The next prime is 133801. The reversal of 133785 is 587331.

It is not a de Polignac number, because 133785 - 2² = 133781 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

133785 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (133781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 361 + ... + 630.

It is an arithmetic number, because the mean of its divisors is an integer number (14880).

2¹³³⁷⁸⁵ is an apocalyptic number.

133785 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

133785 is a deficient number, since it is larger than the sum of its proper divisors (104295).

133785 is an equidigital number, since it uses as much as digits as its factorization.

133785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1005 (or 999 counting only the distinct ones).

The product of its digits is 2520, while the sum is 27.

The square root of 133785 is about 365.7663188431. The cubic root of 133785 is about 51.1449165492.

The spelling of 133785 in words is "one hundred thirty-three thousand, seven hundred eighty-five".