425639 has 4 divisors (see below), whose sum is σ = 427056. Its totient is φ = 424224.

The previous prime is 425609. The next prime is 425641. The reversal of 425639 is 936524.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-425639 is a prime.

It is an Ulam number.

It is a d-powerful number, because it can be written as 4⁴ + 2¹³ + 6⁷ + 5⁷ + 3¹⁰ + 9² .

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (425609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 59 + ... + 924.

It is an arithmetic number, because the mean of its divisors is an integer number (106764).

2⁴²⁵⁶³⁹ is an apocalyptic number.

425639 is a deficient number, since it is larger than the sum of its proper divisors (1417).

425639 is an equidigital number, since it uses as much as digits as its factorization.

425639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1416.

The product of its digits is 6480, while the sum is 29.

The square root of 425639 is about 652.4101470701. The cubic root of 425639 is about 75.2223917588. Note that the first 3 decimals are identical.

The spelling of 425639 in words is "four hundred twenty-five thousand, six hundred thirty-nine".