1678909913 has 4 divisors (see below), whose sum is σ = 1679014308. Its totient is φ = 1678805520.

The previous prime is 1678909823. The next prime is 1678909937. The reversal of 1678909913 is 3199098761.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 86341264 + 1592568649 = 9292^2 + 39907^2 .

It is a cyclic number.

It is not a de Polignac number, because 1678909913 - 2¹² = 1678905817 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1678909313) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22406 + ... + 62127.

It is an arithmetic number, because the mean of its divisors is an integer number (419753577).

Almost surely, 2^1678909913 is an apocalyptic number.

It is an amenable number.

1678909913 is a deficient number, since it is larger than the sum of its proper divisors (104395).

1678909913 is an equidigital number, since it uses as much as digits as its factorization.

1678909913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104394.

The product of its (nonzero) digits is 734832, while the sum is 53.

The square root of 1678909913 is about 40974.5032062623. The cubic root of 1678909913 is about 1188.5272161890.

The spelling of 1678909913 in words is "one billion, six hundred seventy-eight million, nine hundred nine thousand, nine hundred thirteen".