1668785447 has 16 divisors (see below), whose sum is σ = 2094850560. Its totient is φ = 1296184032.

The previous prime is 1668785411. The next prime is 1668785453. The reversal of 1668785447 is 7445878661.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1668785447 - 2⁸ = 1668785191 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1668785392 and 1668785401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1668785477) 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, 269708 + ... + 275825.

It is an arithmetic number, because the mean of its divisors is an integer number (130928160).

Almost surely, 2^1668785447 is an apocalyptic number.

1668785447 is a deficient number, since it is larger than the sum of its proper divisors (426065113).

1668785447 is a wasteful number, since it uses less digits than its factorization.

1668785447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 545582.

The product of its digits is 9031680, while the sum is 56.

The square root of 1668785447 is about 40850.7704578506. The cubic root of 1668785447 is about 1186.1333071162.

The spelling of 1668785447 in words is "one billion, six hundred sixty-eight million, seven hundred eighty-five thousand, four hundred forty-seven".