1566671617 has 4 divisors (see below), whose sum is σ = 1790481856. Its totient is φ = 1342861380.

The previous prime is 1566671609. The next prime is 1566671647. The reversal of 1566671617 is 7161766651.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 7161766651 = 13 ⋅550905127.

It is not a de Polignac number, because 1566671617 - 2³ = 1566671609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1566671647) 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, 111905109 + ... + 111905122.

It is an arithmetic number, because the mean of its divisors is an integer number (447620464).

Almost surely, 2^1566671617 is an apocalyptic number.

It is an amenable number.

1566671617 is a deficient number, since it is larger than the sum of its proper divisors (223810239).

1566671617 is an equidigital number, since it uses as much as digits as its factorization.

1566671617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 223810238.

The product of its digits is 317520, while the sum is 46.

The square root of 1566671617 is about 39581.2028240679. The cubic root of 1566671617 is about 1161.4289803742.

The spelling of 1566671617 in words is "one billion, five hundred sixty-six million, six hundred seventy-one thousand, six hundred seventeen".