2665819 has 4 divisors (see below), whose sum is σ = 2870896. Its totient is φ = 2460744.

The previous prime is 2665811. The next prime is 2665823. The reversal of 2665819 is 9185662.

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

It is not a de Polignac number, because 2665819 - 2³ = 2665811 is a prime.

It is a super-2 number, since 2×2665819² = 14213181881522, which contains 22 as substring.

It is a d-powerful number, because it can be written as 2²¹ + 6² + 6⁴ + 5⁵ + 8⁵ + 1 + 9⁶ .

It is a Duffinian number.

2665819 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (2665811) 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, 102519 + ... + 102544.

It is an arithmetic number, because the mean of its divisors is an integer number (717724).

2^2665819 is an apocalyptic number.

2665819 is a deficient number, since it is larger than the sum of its proper divisors (205077).

2665819 is a wasteful number, since it uses less digits than its factorization.

2665819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 205076.

The product of its digits is 25920, while the sum is 37.

The square root of 2665819 is about 1632.7335973759. The cubic root of 2665819 is about 138.6575598319.

The spelling of 2665819 in words is "two million, six hundred sixty-five thousand, eight hundred nineteen".