638285801 has 4 divisors (see below), whose sum is σ = 638835792. Its totient is φ = 637735812.

The previous prime is 638285789. The next prime is 638285807. The reversal of 638285801 is 108582836.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-638285801 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (638285807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 273251 + ... + 275576.

It is an arithmetic number, because the mean of its divisors is an integer number (159708948).

Almost surely, 2^638285801 is an apocalyptic number.

It is an amenable number.

638285801 is a deficient number, since it is larger than the sum of its proper divisors (549991).

638285801 is a wasteful number, since it uses less digits than its factorization.

638285801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 549990.

The product of its (nonzero) digits is 92160, while the sum is 41.

The square root of 638285801 is about 25264.3187321566. The cubic root of 638285801 is about 861.0037860176.

The spelling of 638285801 in words is "six hundred thirty-eight million, two hundred eighty-five thousand, eight hundred one".