431378639 has 16 divisors (see below), whose sum is σ = 460857600. Its totient is φ = 402912576.

The previous prime is 431378611. The next prime is 431378653. The reversal of 431378639 is 936873134.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-431378639 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 431378639.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (431378659) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 168632 + ... + 171170.

It is an arithmetic number, because the mean of its divisors is an integer number (28803600).

Almost surely, 2^431378639 is an apocalyptic number.

431378639 is a deficient number, since it is larger than the sum of its proper divisors (29478961).

431378639 is a wasteful number, since it uses less digits than its factorization.

431378639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2734.

The product of its digits is 326592, while the sum is 44.

The square root of 431378639 is about 20769.6566895074. The cubic root of 431378639 is about 755.5900181568.

The spelling of 431378639 in words is "four hundred thirty-one million, three hundred seventy-eight thousand, six hundred thirty-nine".