2665444421 has 4 divisors (see below), whose sum is σ = 2682421932. Its totient is φ = 2648466912.

The previous prime is 2665444409. The next prime is 2665444423. The reversal of 2665444421 is 1244445662.

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 845995396 + 1819449025 = 29086^2 + 42655^2 .

It is not a de Polignac number, because 2665444421 - 2¹⁰ = 2665443397 is a prime.

It is a super-2 number, since 2×2665444421² = 14209187922880050482, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2665444423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8488520 + ... + 8488833.

It is an arithmetic number, because the mean of its divisors is an integer number (670605483).

Almost surely, 2^2665444421 is an apocalyptic number.

It is an amenable number.

2665444421 is a deficient number, since it is larger than the sum of its proper divisors (16977511).

2665444421 is a wasteful number, since it uses less digits than its factorization.

2665444421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16977510.

The product of its digits is 184320, while the sum is 38.

The square root of 2665444421 is about 51627.9422502970. The cubic root of 2665444421 is about 1386.5106518710.

The spelling of 2665444421 in words is "two billion, six hundred sixty-five million, four hundred forty-four thousand, four hundred twenty-one".