638406247099 has 2 divisors, whose sum is σ = 638406247100. Its totient is φ = 638406247098.

The previous prime is 638406247049. The next prime is 638406247103. The reversal of 638406247099 is 990742604836.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 638406247099 - 2³¹ = 636258763451 is a prime.

It is not a weakly prime, because it can be changed into another prime (638406247049) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319203123549 + 319203123550.

It is an arithmetic number, because the mean of its divisors is an integer number (319203123550).

Almost surely, 2^638406247099 is an apocalyptic number.

638406247099 is a deficient number, since it is larger than the sum of its proper divisors (1).

638406247099 is an equidigital number, since it uses as much as digits as its factorization.

638406247099 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15676416, while the sum is 58.

The spelling of 638406247099 in words is "six hundred thirty-eight billion, four hundred six million, two hundred forty-seven thousand, ninety-nine".