1605965 has 4 divisors (see below), whose sum is σ = 1927164. Its totient is φ = 1284768.

The previous prime is 1605941. The next prime is 1605971. The reversal of 1605965 is 5695061.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5695061 = 127 ⋅44843.

It can be written as a sum of positive squares in 2 ways, for example, as 609961 + 996004 = 781^2 + 998^2 .

It is a cyclic number.

It is not a de Polignac number, because 1605965 - 2¹² = 1601869 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 160592 + ... + 160601.

It is an arithmetic number, because the mean of its divisors is an integer number (481791).

2^1605965 is an apocalyptic number.

It is an amenable number.

1605965 is a deficient number, since it is larger than the sum of its proper divisors (321199).

1605965 is an equidigital number, since it uses as much as digits as its factorization.

1605965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 321198.

The product of its (nonzero) digits is 8100, while the sum is 32.

The square root of 1605965 is about 1267.2667438231. The cubic root of 1605965 is about 117.1058773249.

The spelling of 1605965 in words is "one million, six hundred five thousand, nine hundred sixty-five".