1687905864 has 80 divisors (see below), whose sum is σ = 4736220720. Its totient is φ = 561621600.

The previous prime is 1687905841. The next prime is 1687905889. The reversal of 1687905864 is 4685097861.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 1687905864.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 414639 + ... + 418689.

It is an arithmetic number, because the mean of its divisors is an integer number (59202759).

Almost surely, 2^1687905864 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1687905864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2368110360).

1687905864 is an abundant number, since it is smaller than the sum of its proper divisors (3048314856).

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

1687905864 is a wasteful number, since it uses less digits than its factorization.

1687905864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4712 (or 4699 counting only the distinct ones).

The product of its (nonzero) digits is 2903040, while the sum is 54.

The square root of 1687905864 is about 41084.1315351803. The cubic root of 1687905864 is about 1190.6462285756.

The spelling of 1687905864 in words is "one billion, six hundred eighty-seven million, nine hundred five thousand, eight hundred sixty-four".