645389 has 8 divisors (see below), whose sum is σ = 675840. Its totient is φ = 615600.

The previous prime is 645383. The next prime is 645397. The reversal of 645389 is 983546.

645389 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-645389 is a prime.

It is a super-2 number, since 2×645389² = 833053922642, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645383) 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, 3284 + ... + 3474.

It is an arithmetic number, because the mean of its divisors is an integer number (84480).

2⁶⁴⁵³⁸⁹ is an apocalyptic number.

It is an amenable number.

645389 is a deficient number, since it is larger than the sum of its proper divisors (30451).

645389 is a wasteful number, since it uses less digits than its factorization.

645389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 331.

The product of its digits is 25920, while the sum is 35.

The square root of 645389 is about 803.3610645283. The cubic root of 645389 is about 86.4185920352.

The spelling of 645389 in words is "six hundred forty-five thousand, three hundred eighty-nine".