1687239820 has 48 divisors (see below), whose sum is σ = 4053692160. Its totient is φ = 577865664.

The previous prime is 1687239787. The next prime is 1687239857. The reversal of 1687239820 is 289327861.

It is a Smith number, since the sum of its digits (46) coincides with the sum of the digits of its prime factors.

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, 136747 + ... + 148573.

It is an arithmetic number, because the mean of its divisors is an integer number (84451920).

Almost surely, 2^1687239820 is an apocalyptic number.

1687239820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1687239820 is an abundant number, since it is smaller than the sum of its proper divisors (2366452340).

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

1687239820 is a wasteful number, since it uses less digits than its factorization.

1687239820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12862 (or 12860 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 46.

The square root of 1687239820 is about 41076.0248807014. The cubic root of 1687239820 is about 1190.4895991638.

The spelling of 1687239820 in words is "one billion, six hundred eighty-seven million, two hundred thirty-nine thousand, eight hundred twenty".