40640065 has 4 divisors (see below), whose sum is σ = 48768084. Its totient is φ = 32512048.

The previous prime is 40640053. The next prime is 40640113. The reversal of 40640065 is 56004604.

It is a happy number.

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 25492401 + 15147664 = 5049^2 + 3892^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-40640065 is a prime.

It is a super-2 number, since 2×40640065² = 3303229766408450, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4064002 + ... + 4064011.

It is an arithmetic number, because the mean of its divisors is an integer number (12192021).

Almost surely, 2^40640065 is an apocalyptic number.

It is an amenable number.

40640065 is a deficient number, since it is larger than the sum of its proper divisors (8128019).

40640065 is an equidigital number, since it uses as much as digits as its factorization.

40640065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8128018.

The product of its (nonzero) digits is 2880, while the sum is 25.

The square root of 40640065 is about 6374.9560782801. The cubic root of 40640065 is about 343.8097046708.

Adding to 40640065 its reverse (56004604), we get a palindrome (96644669).

The spelling of 40640065 in words is "forty million, six hundred forty thousand, sixty-five".