40581281 has 8 divisors (see below), whose sum is σ = 43825320. Its totient is φ = 37354752.

The previous prime is 40581253. The next prime is 40581301. The reversal of 40581281 is 18218504.

It can be written as a sum of positive squares in 4 ways, for example, as 4389025 + 36192256 = 2095^2 + 6016^2 .

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 40581281 - 2⁶ = 40581217 is a prime.

It is a super-2 number, since 2×40581281² = 3293680735201922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40581221) 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, 665 + ... + 9033.

It is an arithmetic number, because the mean of its divisors is an integer number (5478165).

Almost surely, 2^40581281 is an apocalyptic number.

It is an amenable number.

40581281 is a deficient number, since it is larger than the sum of its proper divisors (3244039).

40581281 is a wasteful number, since it uses less digits than its factorization.

40581281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8755.

The product of its (nonzero) digits is 2560, while the sum is 29.

The square root of 40581281 is about 6370.3438682696. The cubic root of 40581281 is about 343.6438563301.

Adding to 40581281 its reverse (18218504), we get a palindrome (58799785).

The spelling of 40581281 in words is "forty million, five hundred eighty-one thousand, two hundred eighty-one".