1687680973 has 16 divisors (see below), whose sum is σ = 1862381376. Its totient is φ = 1516631040.

The previous prime is 1687680949. The next prime is 1687680977. The reversal of 1687680973 is 3790867861.

It is a cyclic number.

It is not a de Polignac number, because 1687680973 - 2⁹ = 1687680461 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1687680977) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 343611 + ... + 348487.

It is an arithmetic number, because the mean of its divisors is an integer number (116398836).

Almost surely, 2^1687680973 is an apocalyptic number.

It is an amenable number.

1687680973 is a deficient number, since it is larger than the sum of its proper divisors (174700403).

1687680973 is a wasteful number, since it uses less digits than its factorization.

1687680973 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5244.

The product of its (nonzero) digits is 3048192, while the sum is 55.

The square root of 1687680973 is about 41081.3944870424. The cubic root of 1687680973 is about 1190.5933469705.

The spelling of 1687680973 in words is "one billion, six hundred eighty-seven million, six hundred eighty thousand, nine hundred seventy-three".