1609665023 has 4 divisors (see below), whose sum is σ = 1609745280. Its totient is φ = 1609584768.

The previous prime is 1609665007. The next prime is 1609665073. The reversal of 1609665023 is 3205669061.

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: 3205669061 = 7 ⋅457952723.

It is a cyclic number.

It is not a de Polignac number, because 1609665023 - 2⁴ = 1609665007 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 (1609665073) 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, 18911 + ... + 59807.

It is an arithmetic number, because the mean of its divisors is an integer number (402436320).

Almost surely, 2^1609665023 is an apocalyptic number.

1609665023 is a deficient number, since it is larger than the sum of its proper divisors (80257).

1609665023 is an equidigital number, since it uses as much as digits as its factorization.

1609665023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80256.

The product of its (nonzero) digits is 58320, while the sum is 38.

The square root of 1609665023 is about 40120.6308898552. The cubic root of 1609665023 is about 1171.9574273403.

The spelling of 1609665023 in words is "one billion, six hundred nine million, six hundred sixty-five thousand, twenty-three".