1666838667 has 8 divisors (see below), whose sum is σ = 2393409424. Its totient is φ = 1025746848.

The previous prime is 1666838611. The next prime is 1666838683. The reversal of 1666838667 is 7668386661.

It is a happy number.

1666838667 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-1666838667 is a prime.

It is a super-2 number, since 2×1666838667² = 5556702283612673778, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1666838167) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21369688 + ... + 21369765.

It is an arithmetic number, because the mean of its divisors is an integer number (299176178).

Almost surely, 2^1666838667 is an apocalyptic number.

1666838667 is a deficient number, since it is larger than the sum of its proper divisors (726570757).

1666838667 is a wasteful number, since it uses less digits than its factorization.

1666838667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42739469.

The product of its digits is 10450944, while the sum is 57.

The square root of 1666838667 is about 40826.9355573009. The cubic root of 1666838667 is about 1185.6718858827.

The spelling of 1666838667 in words is "one billion, six hundred sixty-six million, eight hundred thirty-eight thousand, six hundred sixty-seven".