1686604640 has 96 divisors (see below), whose sum is σ = 4564594944. Its totient is φ = 576898560.

The previous prime is 1686604639. The next prime is 1686604679. The reversal of 1686604640 is 464066861.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 548387 + ... + 551453.

It is an arithmetic number, because the mean of its divisors is an integer number (47547864).

Almost surely, 2^1686604640 is an apocalyptic number.

1686604640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1686604640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2282297472).

1686604640 is an abundant number, since it is smaller than the sum of its proper divisors (2877990304).

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

1686604640 is a wasteful number, since it uses less digits than its factorization.

1686604640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3580 (or 3572 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 41.

The square root of 1686604640 is about 41068.2923920632. The cubic root of 1686604640 is about 1190.3401894425.

The spelling of 1686604640 in words is "one billion, six hundred eighty-six million, six hundred four thousand, six hundred forty".