645434 has 8 divisors (see below), whose sum is σ = 986580. Its totient is φ = 316576.

The previous prime is 645433. The next prime is 645443. The reversal of 645434 is 434546.

It can be written as a sum of positive squares in 2 ways, for example, as 644809 + 625 = 803^2 + 25^2 .

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

It is a Curzon number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 645434.

It is not an unprimeable number, because it can be changed into a prime (645431) 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 3 ways as a sum of consecutive naturals, for example, 2939 + ... + 3150.

2⁶⁴⁵⁴³⁴ is an apocalyptic number.

645434 is a deficient number, since it is larger than the sum of its proper divisors (341146).

645434 is a wasteful number, since it uses less digits than its factorization.

645434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6144.

The product of its digits is 5760, while the sum is 26.

The square root of 645434 is about 803.3890713720. The cubic root of 645434 is about 86.4206005119.

The spelling of 645434 in words is "six hundred forty-five thousand, four hundred thirty-four".