1687171812 has 48 divisors (see below), whose sum is σ = 4068574272. Its totient is φ = 543800320.

The previous prime is 1687171799. The next prime is 1687171813. The reversal of 1687171812 is 2181717861.

It is not an unprimeable number, because it can be changed into a prime (1687171813) 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, 40423 + ... + 70769.

It is an arithmetic number, because the mean of its divisors is an integer number (84761964).

Almost surely, 2^1687171812 is an apocalyptic number.

1687171812 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1687171812 is an abundant number, since it is smaller than the sum of its proper divisors (2381402460).

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

1687171812 is a wasteful number, since it uses less digits than its factorization.

1687171812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30508 (or 30506 counting only the distinct ones).

The product of its digits is 37632, while the sum is 42.

The square root of 1687171812 is about 41075.1970415237. The cubic root of 1687171812 is about 1190.4736038276.

The spelling of 1687171812 in words is "one billion, six hundred eighty-seven million, one hundred seventy-one thousand, eight hundred twelve".