639455347 has 2 divisors, whose sum is σ = 639455348. Its totient is φ = 639455346.

The previous prime is 639455339. The next prime is 639455353. The reversal of 639455347 is 743554936.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 639455347 - 2³ = 639455339 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 639455297 and 639455306.

It is not a weakly prime, because it can be changed into another prime (639456347) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319727673 + 319727674.

It is an arithmetic number, because the mean of its divisors is an integer number (319727674).

Almost surely, 2^639455347 is an apocalyptic number.

639455347 is a deficient number, since it is larger than the sum of its proper divisors (1).

639455347 is an equidigital number, since it uses as much as digits as its factorization.

639455347 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1360800, while the sum is 46.

The square root of 639455347 is about 25287.4543400478. The cubic root of 639455347 is about 861.5293442747.

The spelling of 639455347 in words is "six hundred thirty-nine million, four hundred fifty-five thousand, three hundred forty-seven".