638807057 has 4 divisors (see below), whose sum is σ = 730065216. Its totient is φ = 547548900.

The previous prime is 638807051. The next prime is 638807063. The reversal of 638807057 is 750708836.

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 an interprime number because it is at equal distance from previous prime (638807051) and next prime (638807063).

It is a cyclic number.

It is not a de Polignac number, because 638807057 - 2²⁰ = 637758481 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 638806999 and 638807017.

It is not an unprimeable number, because it can be changed into a prime (638807051) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45629069 + ... + 45629082.

It is an arithmetic number, because the mean of its divisors is an integer number (182516304).

Almost surely, 2^638807057 is an apocalyptic number.

It is an amenable number.

638807057 is a deficient number, since it is larger than the sum of its proper divisors (91258159).

638807057 is an equidigital number, since it uses as much as digits as its factorization.

638807057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91258158.

The product of its (nonzero) digits is 282240, while the sum is 44.

The square root of 638807057 is about 25274.6326778452. The cubic root of 638807057 is about 861.2381017804.

The spelling of 638807057 in words is "six hundred thirty-eight million, eight hundred seven thousand, fifty-seven".