645243 has 8 divisors (see below), whose sum is σ = 883728. Its totient is φ = 418464.

The previous prime is 645233. The next prime is 645257. The reversal of 645243 is 342546.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 645243 - 2⁶ = 645179 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645233) 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, 2796 + ... + 3017.

It is an arithmetic number, because the mean of its divisors is an integer number (110466).

2⁶⁴⁵²⁴³ is an apocalyptic number.

645243 is a deficient number, since it is larger than the sum of its proper divisors (238485).

645243 is a wasteful number, since it uses less digits than its factorization.

645243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5853.

The product of its digits is 2880, while the sum is 24.

The square root of 645243 is about 803.2701911561. The cubic root of 645243 is about 86.4120750013.

Adding to 645243 its reverse (342546), we get a palindrome (987789).

It can be divided in two parts, 645 and 243, that added together give a palindrome (888).

The spelling of 645243 in words is "six hundred forty-five thousand, two hundred forty-three".