639453 has 8 divisors (see below), whose sum is σ = 872608. Its totient is φ = 416304.

The previous prime is 639451. The next prime is 639487. The reversal of 639453 is 354936.

It is a happy number.

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

It is not a de Polignac number, because 639453 - 2¹ = 639451 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 639453.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639451) 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 7 ways as a sum of consecutive naturals, for example, 2350 + ... + 2607.

It is an arithmetic number, because the mean of its divisors is an integer number (109076).

2⁶³⁹⁴⁵³ is an apocalyptic number.

It is an amenable number.

639453 is a deficient number, since it is larger than the sum of its proper divisors (233155).

639453 is a wasteful number, since it uses less digits than its factorization.

639453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5003.

The product of its digits is 9720, while the sum is 30.

The square root of 639453 is about 799.6580519197. The cubic root of 639453 is about 86.1528290247.

The spelling of 639453 in words is "six hundred thirty-nine thousand, four hundred fifty-three".