40505281 has 8 divisors (see below), whose sum is σ = 41287784. Its totient is φ = 39726720.

The previous prime is 40505263. The next prime is 40505299. The reversal of 40505281 is 18250504.

It is an interprime number because it is at equal distance from previous prime (40505263) and next prime (40505299).

It can be written as a sum of positive squares in 4 ways, for example, as 13256881 + 27248400 = 3641^2 + 5220^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 40505281 - 2⁵ = 40505249 is a prime.

It is a super-2 number, since 2×40505281² = 3281355577777922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40505221) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27151 + ... + 28603.

It is an arithmetic number, because the mean of its divisors is an integer number (5160973).

Almost surely, 2^40505281 is an apocalyptic number.

It is an amenable number.

40505281 is a deficient number, since it is larger than the sum of its proper divisors (782503).

40505281 is a wasteful number, since it uses less digits than its factorization.

40505281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1971.

The product of its (nonzero) digits is 1600, while the sum is 25.

The square root of 40505281 is about 6364.3759316998. The cubic root of 40505281 is about 343.4291986257.

Adding to 40505281 its reverse (18250504), we get a palindrome (58755785).

The spelling of 40505281 in words is "forty million, five hundred five thousand, two hundred eighty-one".