1688321904 has 40 divisors (see below), whose sum is σ = 4387635840. Its totient is φ = 559401408.

The previous prime is 1688321897. The next prime is 1688321911. The reversal of 1688321904 is 4091238861.

1688321904 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (1688321897) and next prime (1688321911).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 97294 + ... + 113325.

It is an arithmetic number, because the mean of its divisors is an integer number (109690896).

Almost surely, 2^1688321904 is an apocalyptic number.

It is an amenable number.

1688321904 is an abundant number, since it is smaller than the sum of its proper divisors (2699313936).

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

1688321904 is a wasteful number, since it uses less digits than its factorization.

1688321904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210797 (or 210791 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 42.

The square root of 1688321904 is about 41089.1944919829. The cubic root of 1688321904 is about 1190.7440452003.

The spelling of 1688321904 in words is "one billion, six hundred eighty-eight million, three hundred twenty-one thousand, nine hundred four".