1688564444 has 24 divisors (see below), whose sum is σ = 3378076800. Its totient is φ = 723467376.

The previous prime is 1688564429. The next prime is 1688564477. The reversal of 1688564444 is 4444658861.

It is a junction number, because it is equal to n+sod(n) for n = 1688564392 and 1688564401.

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, 136859 + ... + 148685.

It is an arithmetic number, because the mean of its divisors is an integer number (140753200).

Almost surely, 2^1688564444 is an apocalyptic number.

1688564444 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

1688564444 is an abundant number, since it is smaller than the sum of its proper divisors (1689512356).

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

1688564444 is a wasteful number, since it uses less digits than its factorization.

1688564444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16937 (or 16935 counting only the distinct ones).

The product of its digits is 2949120, while the sum is 50.

The square root of 1688564444 is about 41092.1457702077. The cubic root of 1688564444 is about 1190.8010622165.

The spelling of 1688564444 in words is "one billion, six hundred eighty-eight million, five hundred sixty-four thousand, four hundred forty-four".