640213402441 has 2 divisors, whose sum is σ = 640213402442. Its totient is φ = 640213402440.

The previous prime is 640213402357. The next prime is 640213402469. The reversal of 640213402441 is 144204312046.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 478753286400 + 161460116041 = 691920^2 + 401821^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-640213402441 is a prime.

It is not a weakly prime, because it can be changed into another prime (640213402481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320106701220 + 320106701221.

It is an arithmetic number, because the mean of its divisors is an integer number (320106701221).

Almost surely, 2^640213402441 is an apocalyptic number.

It is an amenable number.

640213402441 is a deficient number, since it is larger than the sum of its proper divisors (1).

640213402441 is an equidigital number, since it uses as much as digits as its factorization.

640213402441 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18432, while the sum is 31.

Adding to 640213402441 its reverse (144204312046), we get a palindrome (784417714487).

The spelling of 640213402441 in words is "six hundred forty billion, two hundred thirteen million, four hundred two thousand, four hundred forty-one".