640643010433 has 4 divisors (see below), whose sum is σ = 641421435328. Its totient is φ = 639864585540.

The previous prime is 640643010373. The next prime is 640643010437. The reversal of 640643010433 is 334010346046.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 640643010433 - 2²⁵ = 640609456001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (640643010437) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 389211213 + ... + 389212858.

It is an arithmetic number, because the mean of its divisors is an integer number (160355358832).

Almost surely, 2^640643010433 is an apocalyptic number.

It is an amenable number.

640643010433 is a deficient number, since it is larger than the sum of its proper divisors (778424895).

640643010433 is an equidigital number, since it uses as much as digits as its factorization.

640643010433 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 778424894.

The product of its (nonzero) digits is 62208, while the sum is 34.

Adding to 640643010433 its reverse (334010346046), we get a palindrome (974653356479).

The spelling of 640643010433 in words is "six hundred forty billion, six hundred forty-three million, ten thousand, four hundred thirty-three".