1616665 has 4 divisors (see below), whose sum is σ = 1940004. Its totient is φ = 1293328.

The previous prime is 1616651. The next prime is 1616669. The reversal of 1616665 is 5666161.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 335241 + 1281424 = 579^2 + 1132^2 .

It is a cyclic number.

It is not a de Polignac number, because 1616665 - 2⁵ = 1616633 is a prime.

It is a super-2 number, since 2×1616665² = 5227211444450, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1616669) 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, 161662 + ... + 161671.

It is an arithmetic number, because the mean of its divisors is an integer number (485001).

2^1616665 is an apocalyptic number.

It is an amenable number.

1616665 is a deficient number, since it is larger than the sum of its proper divisors (323339).

1616665 is an equidigital number, since it uses as much as digits as its factorization.

1616665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 323338.

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

The square root of 1616665 is about 1271.4814194474. The cubic root of 1616665 is about 117.3653807591.

The spelling of 1616665 in words is "one million, six hundred sixteen thousand, six hundred sixty-five".