640435533 has 4 divisors (see below), whose sum is σ = 853914048. Its totient is φ = 426957020.

The previous prime is 640435493. The next prime is 640435559. The reversal of 640435533 is 335534046.

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 640435533 - 2¹⁸ = 640173389 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 640435494 and 640435503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640435573) 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 3 ways as a sum of consecutive naturals, for example, 106739253 + ... + 106739258.

It is an arithmetic number, because the mean of its divisors is an integer number (213478512).

Almost surely, 2^640435533 is an apocalyptic number.

It is an amenable number.

640435533 is a deficient number, since it is larger than the sum of its proper divisors (213478515).

640435533 is a wasteful number, since it uses less digits than its factorization.

640435533 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213478514.

The product of its (nonzero) digits is 64800, while the sum is 33.

The square root of 640435533 is about 25306.8277940954. The cubic root of 640435533 is about 861.9693165615.

Adding to 640435533 its reverse (335534046), we get a palindrome (975969579).

The spelling of 640435533 in words is "six hundred forty million, four hundred thirty-five thousand, five hundred thirty-three".