643572253 has 4 divisors (see below), whose sum is σ = 643696060. Its totient is φ = 643448448.

The previous prime is 643572229. The next prime is 643572257. The reversal of 643572253 is 352275346.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 315346564 + 328225689 = 17758^2 + 18117^2 .

It is a cyclic number.

It is not a de Polignac number, because 643572253 - 2¹⁷ = 643441181 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643572257) 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, 53748 + ... + 64621.

It is an arithmetic number, because the mean of its divisors is an integer number (160924015).

Almost surely, 2^643572253 is an apocalyptic number.

It is an amenable number.

643572253 is a deficient number, since it is larger than the sum of its proper divisors (123807).

643572253 is a wasteful number, since it uses less digits than its factorization.

643572253 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123806.

The product of its digits is 151200, while the sum is 37.

The square root of 643572253 is about 25368.7258844428. The cubic root of 643572253 is about 863.3742741161.

The spelling of 643572253 in words is "six hundred forty-three million, five hundred seventy-two thousand, two hundred fifty-three".