641663357 has 4 divisors (see below), whose sum is σ = 650453340. Its totient is φ = 632873376.

The previous prime is 641663353. The next prime is 641663369. The reversal of 641663357 is 753366146.

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 333099001 + 308564356 = 18251^2 + 17566^2 .

It is a cyclic number.

It is not a de Polignac number, because 641663357 - 2² = 641663353 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 (641663353) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4394882 + ... + 4395027.

It is an arithmetic number, because the mean of its divisors is an integer number (162613335).

Almost surely, 2^641663357 is an apocalyptic number.

It is an amenable number.

641663357 is a deficient number, since it is larger than the sum of its proper divisors (8789983).

641663357 is an equidigital number, since it uses as much as digits as its factorization.

641663357 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8789982.

The product of its digits is 272160, while the sum is 41.

The square root of 641663357 is about 25331.0749278431. The cubic root of 641663357 is about 862.5198122453.

The spelling of 641663357 in words is "six hundred forty-one million, six hundred sixty-three thousand, three hundred fifty-seven".