145645 has 4 divisors (see below), whose sum is σ = 174780. Its totient is φ = 116512.

The previous prime is 145643. The next prime is 145661. The reversal of 145645 is 546541.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 546541 = 383 ⋅1427.

It can be written as a sum of positive squares in 2 ways, for example, as 44521 + 101124 = 211^2 + 318^2 .

It is a cyclic number.

It is not a de Polignac number, because 145645 - 2¹ = 145643 is a prime.

It is a super-3 number, since 3×145645³ = 9268468842633375, which contains 333 as substring.

It is an Ulam number.

145645 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (145643) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14560 + ... + 14569.

It is an arithmetic number, because the mean of its divisors is an integer number (43695).

2¹⁴⁵⁶⁴⁵ is an apocalyptic number.

It is an amenable number.

145645 is a deficient number, since it is larger than the sum of its proper divisors (29135).

145645 is an equidigital number, since it uses as much as digits as its factorization.

145645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29134.

The product of its digits is 2400, while the sum is 25.

The square root of 145645 is about 381.6346420335. The cubic root of 145645 is about 52.6136615326.

The spelling of 145645 in words is "one hundred forty-five thousand, six hundred forty-five".