6642565 has 8 divisors (see below), whose sum is σ = 7993368. Its totient is φ = 5299200.

The previous prime is 6642553. The next prime is 6642593. The reversal of 6642565 is 5652466.

It can be written as a sum of positive squares in 4 ways, for example, as 4190209 + 2452356 = 2047^2 + 1566^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 6642565 - 2¹⁵ = 6609797 is a prime.

It is a Duffinian number.

6642565 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 6642565.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 349 + ... + 3661.

It is an arithmetic number, because the mean of its divisors is an integer number (999171).

Almost surely, 2^6642565 is an apocalyptic number.

It is an amenable number.

6642565 is a deficient number, since it is larger than the sum of its proper divisors (1350803).

6642565 is a wasteful number, since it uses less digits than its factorization.

6642565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3719.

The product of its digits is 43200, while the sum is 34.

The square root of 6642565 is about 2577.3174038135. The cubic root of 6642565 is about 187.9801265397.

Subtracting from 6642565 its reverse (5652466), we obtain a palindrome (990099).

The spelling of 6642565 in words is "six million, six hundred forty-two thousand, five hundred sixty-five".