1687534638 has 32 divisors (see below), whose sum is σ = 3435419520. Its totient is φ = 552470880.

The previous prime is 1687534637. The next prime is 1687534729. The reversal of 1687534638 is 8364357861.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1687534637) 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, 753256 + ... + 755492.

It is an arithmetic number, because the mean of its divisors is an integer number (107356860).

Almost surely, 2^1687534638 is an apocalyptic number.

1687534638 is an abundant number, since it is smaller than the sum of its proper divisors (1747884882).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1687534638 is a wasteful number, since it uses less digits than its factorization.

1687534638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4432.

The product of its digits is 2903040, while the sum is 51.

The square root of 1687534638 is about 41079.6134110339. The cubic root of 1687534638 is about 1190.5589347571.

The spelling of 1687534638 in words is "one billion, six hundred eighty-seven million, five hundred thirty-four thousand, six hundred thirty-eight".