641653553 has 2 divisors, whose sum is σ = 641653554. Its totient is φ = 641653552.

The previous prime is 641653547. The next prime is 641653619. The reversal of 641653553 is 355356146.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 359178304 + 282475249 = 18952^2 + 16807^2 .

It is a cyclic number.

It is not a de Polignac number, because 641653553 - 2⁶ = 641653489 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (641653513) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320826776 + 320826777.

It is an arithmetic number, because the mean of its divisors is an integer number (320826777).

Almost surely, 2^641653553 is an apocalyptic number.

It is an amenable number.

641653553 is a deficient number, since it is larger than the sum of its proper divisors (1).

641653553 is an equidigital number, since it uses as much as digits as its factorization.

641653553 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 162000, while the sum is 38.

The square root of 641653553 is about 25330.8814098523. The cubic root of 641653553 is about 862.5154193981.

The spelling of 641653553 in words is "six hundred forty-one million, six hundred fifty-three thousand, five hundred fifty-three".