75645 has 18 divisors (see below), whose sum is σ = 134394. Its totient is φ = 39360.

The previous prime is 75641. The next prime is 75653. The reversal of 75645 is 54657.

It can be written as a sum of positive squares in 3 ways, for example, as 4356 + 71289 = 66^2 + 267^2 .

It is not a de Polignac number, because 75645 - 2² = 75641 is a prime.

75645 is a lucky number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (75641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 1825 + ... + 1865.

2⁷⁵⁶⁴⁵ is an apocalyptic number.

It is an amenable number.

75645 is a deficient number, since it is larger than the sum of its proper divisors (58749).

75645 is a wasteful number, since it uses less digits than its factorization.

75645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93 (or 49 counting only the distinct ones).

The product of its digits is 4200, while the sum is 27.

The square root of 75645 is about 275.0363612325. The cubic root of 75645 is about 42.2921803697.

It can be divided in two parts, 7564 and 5, that added together give a square (7569 = 87²).

The spelling of 75645 in words is "seventy-five thousand, six hundred forty-five".