638280001 has 2 divisors, whose sum is σ = 638280002. Its totient is φ = 638280000.

The previous prime is 638279951. The next prime is 638280037. The reversal of 638280001 is 100082836.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 635796225 + 2483776 = 25215^2 + 1576^2 .

It is a cyclic number.

It is not a de Polignac number, because 638280001 - 2²¹ = 636182849 is a prime.

It is not a weakly prime, because it can be changed into another prime (638283001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319140000 + 319140001.

It is an arithmetic number, because the mean of its divisors is an integer number (319140001).

Almost surely, 2^638280001 is an apocalyptic number.

It is an amenable number.

638280001 is a deficient number, since it is larger than the sum of its proper divisors (1).

638280001 is an equidigital number, since it uses as much as digits as its factorization.

638280001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 638280001 is about 25264.2039455036. The cubic root of 638280001 is about 861.0011780755.

The spelling of 638280001 in words is "six hundred thirty-eight million, two hundred eighty thousand, one".