431640 has 96 divisors (see below), whose sum is σ = 1544400. Its totient is φ = 103680.

The previous prime is 431621. The next prime is 431657. The reversal of 431640 is 46134.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

431640 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3906 + ... + 4014.

2⁴³¹⁶⁴⁰ is an apocalyptic number.

431640 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 431640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (772200).

431640 is an abundant number, since it is smaller than the sum of its proper divisors (1112760).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

431640 is a wasteful number, since it uses less digits than its factorization.

431640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137 (or 130 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 431640 is about 656.9931506492. The cubic root of 431640 is about 75.5742584739.

Adding to 431640 its reverse (46134), we get a palindrome (477774).

It can be divided in two parts, 4316 and 40, that added together give a square (4356 = 66²).

The spelling of 431640 in words is "four hundred thirty-one thousand, six hundred forty".