641544493 has 2 divisors, whose sum is σ = 641544494. Its totient is φ = 641544492.

The previous prime is 641544479. The next prime is 641544499. The reversal of 641544493 is 394445146.

641544493 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 396089604 + 245454889 = 19902^2 + 15667^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-641544493 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (641544499) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320772246 + 320772247.

It is an arithmetic number, because the mean of its divisors is an integer number (320772247).

Almost surely, 2^641544493 is an apocalyptic number.

It is an amenable number.

641544493 is a deficient number, since it is larger than the sum of its proper divisors (1).

641544493 is an equidigital number, since it uses as much as digits as its factorization.

641544493 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 207360, while the sum is 40.

The square root of 641544493 is about 25328.7286100191. The cubic root of 641544493 is about 862.4665502115.

The spelling of 641544493 in words is "six hundred forty-one million, five hundred forty-four thousand, four hundred ninety-three".