1686161378 has 32 divisors (see below), whose sum is σ = 2841378048. Its totient is φ = 750074160.

The previous prime is 1686161369. The next prime is 1686161383. The reversal of 1686161378 is 8731616861.

It is a Harshad number since it is a multiple of its sum of digits (47).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 118376 + ... + 131852.

It is an arithmetic number, because the mean of its divisors is an integer number (88793064).

Almost surely, 2^1686161378 is an apocalyptic number.

1686161378 is a deficient number, since it is larger than the sum of its proper divisors (1155216670).

1686161378 is a wasteful number, since it uses less digits than its factorization.

1686161378 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13559 (or 13537 counting only the distinct ones).

The product of its digits is 290304, while the sum is 47.

The square root of 1686161378 is about 41062.8953923125. The cubic root of 1686161378 is about 1190.2359012590.

The spelling of 1686161378 in words is "one billion, six hundred eighty-six million, one hundred sixty-one thousand, three hundred seventy-eight".