645446 has 8 divisors (see below), whose sum is σ = 974064. Its totient is φ = 320760.

The previous prime is 645443. The next prime is 645467. The reversal of 645446 is 644546.

645446 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 congruent number.

It is not an unprimeable number, because it can be changed into a prime (645443) 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, 530 + ... + 1253.

It is an arithmetic number, because the mean of its divisors is an integer number (121758).

2⁶⁴⁵⁴⁴⁶ is an apocalyptic number.

645446 is a deficient number, since it is larger than the sum of its proper divisors (328618).

645446 is a wasteful number, since it uses less digits than its factorization.

645446 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1966.

The product of its digits is 11520, while the sum is 29.

The square root of 645446 is about 803.3965396988. The cubic root of 645446 is about 86.4211360899.

Subtracting from 645446 its reverse (644546), we obtain a square (900 = 30²).

The spelling of 645446 in words is "six hundred forty-five thousand, four hundred forty-six".