1611916661 has 8 divisors (see below), whose sum is σ = 1697857920. Its totient is φ = 1526085792.

The previous prime is 1611916651. The next prime is 1611916667. The reversal of 1611916661 is 1666191161.

It is a happy number.

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 1611916661 - 2⁶ = 1611916597 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1611916667) 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, 3281 + ... + 56873.

It is an arithmetic number, because the mean of its divisors is an integer number (212232240).

Almost surely, 2^1611916661 is an apocalyptic number.

It is an amenable number.

1611916661 is a deficient number, since it is larger than the sum of its proper divisors (85941259).

1611916661 is a wasteful number, since it uses less digits than its factorization.

1611916661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55195.

The product of its digits is 11664, while the sum is 38.

The square root of 1611916661 is about 40148.6819335330. The cubic root of 1611916661 is about 1172.5036267832.

The spelling of 1611916661 in words is "one billion, six hundred eleven million, nine hundred sixteen thousand, six hundred sixty-one".