1680644380 has 24 divisors (see below), whose sum is σ = 3530212560. Its totient is φ = 672094080.

The previous prime is 1680644359. The next prime is 1680644393. The reversal of 1680644380 is 834460861.

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 7 ways as a sum of consecutive naturals, for example, 106395 + ... + 121165.

It is an arithmetic number, because the mean of its divisors is an integer number (147092190).

Almost surely, 2^1680644380 is an apocalyptic number.

1680644380 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1680644380 is an abundant number, since it is smaller than the sum of its proper divisors (1849568180).

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

1680644380 is a wasteful number, since it uses less digits than its factorization.

1680644380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20469 (or 20467 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 40.

The square root of 1680644380 is about 40995.6629413405. The cubic root of 1680644380 is about 1188.9363609826.

The spelling of 1680644380 in words is "one billion, six hundred eighty million, six hundred forty-four thousand, three hundred eighty".