1666722349 has 8 divisors (see below), whose sum is σ = 1690595712. Its totient is φ = 1642877280.

The previous prime is 1666722289. The next prime is 1666722353. The reversal of 1666722349 is 9432276661.

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

It is a cyclic number.

It is not a de Polignac number, because 1666722349 - 2⁷ = 1666722221 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1666722299 and 1666722308.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666722359) 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, 130482 + ... + 142684.

It is an arithmetic number, because the mean of its divisors is an integer number (211324464).

Almost surely, 2^1666722349 is an apocalyptic number.

It is an amenable number.

1666722349 is a deficient number, since it is larger than the sum of its proper divisors (23873363).

1666722349 is a wasteful number, since it uses less digits than its factorization.

1666722349 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14147.

The product of its digits is 653184, while the sum is 46.

The square root of 1666722349 is about 40825.5110072121. The cubic root of 1666722349 is about 1185.6443050909.

The spelling of 1666722349 in words is "one billion, six hundred sixty-six million, seven hundred twenty-two thousand, three hundred forty-nine".