638927099939 has 2 divisors, whose sum is σ = 638927099940. Its totient is φ = 638927099938.

The previous prime is 638927099873. The next prime is 638927099947. The reversal of 638927099939 is 939990729836.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 638927099939 - 2¹² = 638927095843 is a prime.

It is not a weakly prime, because it can be changed into another prime (638927099989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319463549969 + 319463549970.

It is an arithmetic number, because the mean of its divisors is an integer number (319463549970).

Almost surely, 2^638927099939 is an apocalyptic number.

638927099939 is a deficient number, since it is larger than the sum of its proper divisors (1).

638927099939 is an equidigital number, since it uses as much as digits as its factorization.

638927099939 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 357128352, while the sum is 74.

The spelling of 638927099939 in words is "six hundred thirty-eight billion, nine hundred twenty-seven million, ninety-nine thousand, nine hundred thirty-nine".