1688985984 has 256 divisors, whose sum is σ = 5428684800. Its totient is φ = 455024640.

The previous prime is 1688985983. The next prime is 1688985997. The reversal of 1688985984 is 4895898861.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1688985983) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 3663514 + ... + 3663974.

It is an arithmetic number, because the mean of its divisors is an integer number (21205800).

Almost surely, 2^1688985984 is an apocalyptic number.

1688985984 is a gapful number since it is divisible by the number (14) 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 1688985984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2714342400).

1688985984 is an abundant number, since it is smaller than the sum of its proper divisors (3739698816).

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

1688985984 is a wasteful number, since it uses less digits than its factorization.

1688985984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 561 (or 549 counting only the distinct ones).

The product of its digits is 39813120, while the sum is 66.

The square root of 1688985984 is about 41097.2746541665. The cubic root of 1688985984 is about 1190.9001460894.

The spelling of 1688985984 in words is "one billion, six hundred eighty-eight million, nine hundred eighty-five thousand, nine hundred eighty-four".