1656160321 has 4 divisors (see below), whose sum is σ = 1656274644. Its totient is φ = 1656046000.

The previous prime is 1656160307. The next prime is 1656160357. The reversal of 1656160321 is 1230616561.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1230616561 = 307 ⋅4008523.

It can be written as a sum of positive squares in 2 ways, for example, as 729810225 + 926350096 = 27015^2 + 30436^2 .

It is a cyclic number.

It is not a de Polignac number, because 1656160321 - 2⁷ = 1656160193 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1656160301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31630 + ... + 65671.

It is an arithmetic number, because the mean of its divisors is an integer number (414068661).

Almost surely, 2^1656160321 is an apocalyptic number.

It is an amenable number.

1656160321 is a deficient number, since it is larger than the sum of its proper divisors (114323).

1656160321 is an equidigital number, since it uses as much as digits as its factorization.

1656160321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114322.

The product of its (nonzero) digits is 6480, while the sum is 31.

The square root of 1656160321 is about 40695.9496878989. The cubic root of 1656160321 is about 1183.1345180939.

Adding to 1656160321 its reverse (1230616561), we get a palindrome (2886776882).

The spelling of 1656160321 in words is "one billion, six hundred fifty-six million, one hundred sixty thousand, three hundred twenty-one".