639450019441 has 2 divisors, whose sum is σ = 639450019442. Its totient is φ = 639450019440.

The previous prime is 639450019387. The next prime is 639450019489. The reversal of 639450019441 is 144910054936.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 593972324416 + 45477695025 = 770696^2 + 213255^2 .

It is a cyclic number.

It is not a de Polignac number, because 639450019441 - 2⁹ = 639450018929 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 639450019391 and 639450019400.

It is not a weakly prime, because it can be changed into another prime (639450019141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319725009720 + 319725009721.

It is an arithmetic number, because the mean of its divisors is an integer number (319725009721).

Almost surely, 2^639450019441 is an apocalyptic number.

It is an amenable number.

639450019441 is a deficient number, since it is larger than the sum of its proper divisors (1).

639450019441 is an equidigital number, since it uses as much as digits as its factorization.

639450019441 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 466560, while the sum is 46.

The spelling of 639450019441 in words is "six hundred thirty-nine billion, four hundred fifty million, nineteen thousand, four hundred forty-one".