431640643 has 8 divisors (see below), whose sum is σ = 493961312. Its totient is φ = 369484416.

The previous prime is 431640623. The next prime is 431640647. The reversal of 431640643 is 346046134.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 431640643 - 2¹³ = 431632451 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (431640647) 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 7 ways as a sum of consecutive naturals, for example, 35430 + ... + 46027.

It is an arithmetic number, because the mean of its divisors is an integer number (61745164).

Almost surely, 2^431640643 is an apocalyptic number.

431640643 is a deficient number, since it is larger than the sum of its proper divisors (62320669).

431640643 is an equidigital number, since it uses as much as digits as its factorization.

431640643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82221.

The product of its (nonzero) digits is 20736, while the sum is 31.

The square root of 431640643 is about 20775.9631064362. The cubic root of 431640643 is about 755.7429600067.

Adding to 431640643 its reverse (346046134), we get a palindrome (777686777).

The spelling of 431640643 in words is "four hundred thirty-one million, six hundred forty thousand, six hundred forty-three".