638263852 has 6 divisors (see below), whose sum is σ = 1116961748. Its totient is φ = 319131924.

The previous prime is 638263849. The next prime is 638263859. The reversal of 638263852 is 258362836.

It is a junction number, because it is equal to n+sod(n) for n = 638263799 and 638263808.

It is not an unprimeable number, because it can be changed into a prime (638263859) 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, 79782978 + ... + 79782985.

Almost surely, 2^638263852 is an apocalyptic number.

It is an amenable number.

638263852 is a deficient number, since it is larger than the sum of its proper divisors (478697896).

638263852 is a wasteful number, since it uses less digits than its factorization.

638263852 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 159565967 (or 159565965 counting only the distinct ones).

The product of its digits is 414720, while the sum is 43.

The square root of 638263852 is about 25263.8843410905. The cubic root of 638263852 is about 860.9939166724.

The spelling of 638263852 in words is "six hundred thirty-eight million, two hundred sixty-three thousand, eight hundred fifty-two".