638487877 has 8 divisors (see below), whose sum is σ = 648604800. Its totient is φ = 628402320.

The previous prime is 638487841. The next prime is 638487881. The reversal of 638487877 is 778784836.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-638487877 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638487827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35023 + ... + 50035.

It is an arithmetic number, because the mean of its divisors is an integer number (81075600).

Almost surely, 2^638487877 is an apocalyptic number.

It is an amenable number.

638487877 is a deficient number, since it is larger than the sum of its proper divisors (10116923).

638487877 is a wasteful number, since it uses less digits than its factorization.

638487877 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15683.

The product of its digits is 12644352, while the sum is 58.

The square root of 638487877 is about 25268.3176527445. The cubic root of 638487877 is about 861.0946386539.

The spelling of 638487877 in words is "six hundred thirty-eight million, four hundred eighty-seven thousand, eight hundred seventy-seven".