1656511617 has 4 divisors (see below), whose sum is σ = 2208682160. Its totient is φ = 1104341076.

The previous prime is 1656511573. The next prime is 1656511667. The reversal of 1656511617 is 7161156561.

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.

It is not a de Polignac number, because 1656511617 - 2⁸ = 1656511361 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1656511667) 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, 276085267 + ... + 276085272.

It is an arithmetic number, because the mean of its divisors is an integer number (552170540).

Almost surely, 2^1656511617 is an apocalyptic number.

It is an amenable number.

1656511617 is a deficient number, since it is larger than the sum of its proper divisors (552170543).

1656511617 is an equidigital number, since it uses as much as digits as its factorization.

1656511617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 552170542.

The product of its digits is 37800, while the sum is 39.

The square root of 1656511617 is about 40700.2655642442. The cubic root of 1656511617 is about 1183.2181655996.

It can be divided in two parts, 16565 and 11617, that added together give a palindrome (28182).

The spelling of 1656511617 in words is "one billion, six hundred fifty-six million, five hundred eleven thousand, six hundred seventeen".