638486877 has 16 divisors (see below), whose sum is σ = 1015234560. Its totient is φ = 348986352.

The previous prime is 638486873. The next prime is 638486897. The reversal of 638486877 is 778684836.

It is not a de Polignac number, because 638486877 - 2² = 638486873 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638486873) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 660477 + ... + 661442.

It is an arithmetic number, because the mean of its divisors is an integer number (63452160).

Almost surely, 2^638486877 is an apocalyptic number.

It is an amenable number.

638486877 is a deficient number, since it is larger than the sum of its proper divisors (376747683).

638486877 is a wasteful number, since it uses less digits than its factorization.

638486877 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1321952.

The product of its digits is 10838016, while the sum is 57.

The square root of 638486877 is about 25268.2978651115. The cubic root of 638486877 is about 861.0941891047.

The spelling of 638486877 in words is "six hundred thirty-eight million, four hundred eighty-six thousand, eight hundred seventy-seven".