1686793780971 has 24 divisors (see below), whose sum is σ = 2687899040736. Its totient is φ = 1012709208960.

The previous prime is 1686793780963. The next prime is 1686793781017. The reversal of 1686793780971 is 1790873976861.

1686793780971 is a `hidden beast` number, since 168 + 6 + 7 + 9 + 378 + 0 + 97 + 1 = 666.

It is not a de Polignac number, because 1686793780971 - 2³ = 1686793780963 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1686793780971.

It is not an unprimeable number, because it can be changed into a prime (1686793730971) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 175812775 + ... + 175822368.

It is an arithmetic number, because the mean of its divisors is an integer number (111995793364).

Almost surely, 2^{1686793780971} is an apocalyptic number.

1686793780971 is a deficient number, since it is larger than the sum of its proper divisors (1001105259765).

1686793780971 is a wasteful number, since it uses less digits than its factorization.

1686793780971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 351635203 (or 351635200 counting only the distinct ones).

The product of its (nonzero) digits is 192036096, while the sum is 72.

The spelling of 1686793780971 in words is "one trillion, six hundred eighty-six billion, seven hundred ninety-three million, seven hundred eighty thousand, nine hundred seventy-one".