643245621013 has 2 divisors, whose sum is σ = 643245621014. Its totient is φ = 643245621012.

The previous prime is 643245621001. The next prime is 643245621061. The reversal of 643245621013 is 310126542346.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 607017066769 + 36228554244 = 779113^2 + 190338^2 .

It is a cyclic number.

It is not a de Polignac number, because 643245621013 - 2⁵ = 643245620981 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (643245628013) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321622810506 + 321622810507.

It is an arithmetic number, because the mean of its divisors is an integer number (321622810507).

Almost surely, 2^643245621013 is an apocalyptic number.

It is an amenable number.

643245621013 is a deficient number, since it is larger than the sum of its proper divisors (1).

643245621013 is an equidigital number, since it uses as much as digits as its factorization.

643245621013 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 103680, while the sum is 37.

The spelling of 643245621013 in words is "six hundred forty-three billion, two hundred forty-five million, six hundred twenty-one thousand, thirteen".