1688385647 has 8 divisors (see below), whose sum is σ = 1822941120. Its totient is φ = 1554498720.

The previous prime is 1688385637. The next prime is 1688385689. The reversal of 1688385647 is 7465838861.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1688385647 - 2⁴ = 1688385631 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1688385592 and 1688385601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1688385607) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 161879 + ... + 171992.

It is an arithmetic number, because the mean of its divisors is an integer number (227867640).

Almost surely, 2^1688385647 is an apocalyptic number.

1688385647 is a deficient number, since it is larger than the sum of its proper divisors (134555473).

1688385647 is a wasteful number, since it uses less digits than its factorization.

1688385647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 334273.

The product of its digits is 7741440, while the sum is 56.

The square root of 1688385647 is about 41089.9701508775. The cubic root of 1688385647 is about 1190.7590306211.

The spelling of 1688385647 in words is "one billion, six hundred eighty-eight million, three hundred eighty-five thousand, six hundred forty-seven".