643541253 has 8 divisors (see below), whose sum is σ = 858728928. Its totient is φ = 428690544.

The previous prime is 643541251. The next prime is 643541257. The reversal of 643541253 is 352145346.

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

It is not a de Polignac number, because 643541253 - 2¹ = 643541251 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643541251) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 79750 + ... + 87447.

It is an arithmetic number, because the mean of its divisors is an integer number (107341116).

Almost surely, 2^643541253 is an apocalyptic number.

It is an amenable number.

643541253 is a deficient number, since it is larger than the sum of its proper divisors (215187675).

643541253 is a wasteful number, since it uses less digits than its factorization.

643541253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168483.

The product of its digits is 43200, while the sum is 33.

The square root of 643541253 is about 25368.1148885762. The cubic root of 643541253 is about 863.3604113721.

Adding to 643541253 its reverse (352145346), we get a palindrome (995686599).

The spelling of 643541253 in words is "six hundred forty-three million, five hundred forty-one thousand, two hundred fifty-three".