431639 has 4 divisors (see below), whose sum is σ = 464856. Its totient is φ = 398424.

The previous prime is 431621. The next prime is 431657. The reversal of 431639 is 936134.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 936134 = 2 ⋅468067.

It is an interprime number because it is at equal distance from previous prime (431621) and next prime (431657).

It is not a de Polignac number, because 431639 - 2¹⁶ = 366103 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (431659) 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, 16589 + ... + 16614.

It is an arithmetic number, because the mean of its divisors is an integer number (116214).

2⁴³¹⁶³⁹ is an apocalyptic number.

431639 is a deficient number, since it is larger than the sum of its proper divisors (33217).

431639 is a wasteful number, since it uses less digits than its factorization.

431639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33216.

The product of its digits is 1944, while the sum is 26.

The square root of 431639 is about 656.9923896058. The cubic root of 431639 is about 75.5742001117.

The spelling of 431639 in words is "four hundred thirty-one thousand, six hundred thirty-nine".