1684591380 has 36 divisors (see below), whose sum is σ = 5109927732. Its totient is φ = 449224320.

The previous prime is 1684591361. The next prime is 1684591397. The reversal of 1684591380 is 831954861.

1684591380 is a `hidden beast` number, since 1 + 68 + 459 + 138 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 468116496 + 1216474884 = 21636^2 + 34878^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (45).

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 11 ways as a sum of consecutive naturals, for example, 4679241 + ... + 4679600.

It is an arithmetic number, because the mean of its divisors is an integer number (141942437).

Almost surely, 2^1684591380 is an apocalyptic number.

1684591380 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1684591380 is an abundant number, since it is smaller than the sum of its proper divisors (3425336352).

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

1684591380 is a wasteful number, since it uses less digits than its factorization.

1684591380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9358856 (or 9358851 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 45.

The square root of 1684591380 is about 41043.7739492849. The cubic root of 1684591380 is about 1189.8663739041.

The spelling of 1684591380 in words is "one billion, six hundred eighty-four million, five hundred ninety-one thousand, three hundred eighty".