1966565 has 16 divisors (see below), whose sum is σ = 2476656. Its totient is φ = 1497600.

The previous prime is 1966561. The next prime is 1966583. The reversal of 1966565 is 5656691.

1966565 = T₂₈₉ + T₂₉₀ + ... + T₃₂₉.

It can be written as a sum of positive squares in 8 ways, for example, as 588289 + 1378276 = 767^2 + 1174^2 .

It is not a de Polignac number, because 1966565 - 2² = 1966561 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a Curzon number.

It is a plaindrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1966561) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10775 + ... + 10955.

It is an arithmetic number, because the mean of its divisors is an integer number (154791).

2^1966565 is an apocalyptic number.

It is an amenable number.

1966565 is a deficient number, since it is larger than the sum of its proper divisors (510091).

1966565 is a wasteful number, since it uses less digits than its factorization.

1966565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 280.

The product of its digits is 48600, while the sum is 38.

The square root of 1966565 is about 1402.3426827990. The cubic root of 1966565 is about 125.2860648359.

The spelling of 1966565 in words is "one million, nine hundred sixty-six thousand, five hundred sixty-five".