639225515447 has 2 divisors, whose sum is σ = 639225515448. Its totient is φ = 639225515446.

The previous prime is 639225515429. The next prime is 639225515483. The reversal of 639225515447 is 744515522936.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 639225515447 - 2¹⁴ = 639225499063 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (639225515947) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319612757723 + 319612757724.

It is an arithmetic number, because the mean of its divisors is an integer number (319612757724).

Almost surely, 2^639225515447 is an apocalyptic number.

639225515447 is a deficient number, since it is larger than the sum of its proper divisors (1).

639225515447 is an equidigital number, since it uses as much as digits as its factorization.

639225515447 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9072000, while the sum is 53.

The spelling of 639225515447 in words is "six hundred thirty-nine billion, two hundred twenty-five million, five hundred fifteen thousand, four hundred forty-seven".