638820007783 has 2 divisors, whose sum is σ = 638820007784. Its totient is φ = 638820007782.

The previous prime is 638820007747. The next prime is 638820007801. The reversal of 638820007783 is 387700028836.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 638820007783 - 2²⁵ = 638786453351 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 638820007783.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (638820007583) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319410003891 + 319410003892.

It is an arithmetic number, because the mean of its divisors is an integer number (319410003892).

Almost surely, 2^638820007783 is an apocalyptic number.

638820007783 is a deficient number, since it is larger than the sum of its proper divisors (1).

638820007783 is an equidigital number, since it uses as much as digits as its factorization.

638820007783 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2709504, while the sum is 52.

The spelling of 638820007783 in words is "six hundred thirty-eight billion, eight hundred twenty million, seven thousand, seven hundred eighty-three".