431683728 has 120 divisors (see below), whose sum is σ = 1322111808. Its totient is φ = 120976128.

The previous prime is 431683723. The next prime is 431683789. The reversal of 431683728 is 827386134.

It is a Cunningham number, because it is equal to 20777²-1.

It is a super-3 number, since 3×431683728³ (a number of 27 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 431683728.

It is not an unprimeable number, because it can be changed into a prime (431683723) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 122925 + ... + 126387.

Almost surely, 2^431683728 is an apocalyptic number.

431683728 is a gapful number since it is divisible by the number (48) 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 431683728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (661055904).

431683728 is an abundant number, since it is smaller than the sum of its proper divisors (890428080).

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

431683728 is a wasteful number, since it uses less digits than its factorization.

431683728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3541 (or 3528 counting only the distinct ones).

The product of its digits is 193536, while the sum is 42.

The square root of 431683728 is about 20776.9999759349. Note that the first 4 decimals coincide. The cubic root of 431683728 is about 755.7681044586.

The spelling of 431683728 in words is "four hundred thirty-one million, six hundred eighty-three thousand, seven hundred twenty-eight".