640454505841 has 2 divisors, whose sum is σ = 640454505842. Its totient is φ = 640454505840.

The previous prime is 640454505797. The next prime is 640454505869. The reversal of 640454505841 is 148505454046.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 600346032400 + 40108473441 = 774820^2 + 200271^2 .

It is a cyclic number.

It is not a de Polignac number, because 640454505841 - 2²⁹ = 639917634929 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 640454505791 and 640454505800.

It is not a weakly prime, because it can be changed into another prime (640454505881) 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, 320227252920 + 320227252921.

It is an arithmetic number, because the mean of its divisors is an integer number (320227252921).

Almost surely, 2^640454505841 is an apocalyptic number.

It is an amenable number.

640454505841 is a deficient number, since it is larger than the sum of its proper divisors (1).

640454505841 is an equidigital number, since it uses as much as digits as its factorization.

640454505841 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1536000, while the sum is 46.

Adding to 640454505841 its reverse (148505454046), we get a palindrome (788959959887).

The spelling of 640454505841 in words is "six hundred forty billion, four hundred fifty-four million, five hundred five thousand, eight hundred forty-one".