641971513 has 2 divisors, whose sum is σ = 641971514. Its totient is φ = 641971512.

The previous prime is 641971471. The next prime is 641971531. The reversal of 641971513 is 315179146.

It is a happy number.

641971513 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

Together with next prime (641971531) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 581629689 + 60341824 = 24117^2 + 7768^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-641971513 is a prime.

It is not a weakly prime, because it can be changed into another prime (641971013) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320985756 + 320985757.

It is an arithmetic number, because the mean of its divisors is an integer number (320985757).

Almost surely, 2^641971513 is an apocalyptic number.

It is an amenable number.

641971513 is a deficient number, since it is larger than the sum of its proper divisors (1).

641971513 is an equidigital number, since it uses as much as digits as its factorization.

641971513 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 22680, while the sum is 37.

The square root of 641971513 is about 25337.1567662988. The cubic root of 641971513 is about 862.6578639279.

The spelling of 641971513 in words is "six hundred forty-one million, nine hundred seventy-one thousand, five hundred thirteen".