40143281 has 4 divisors (see below), whose sum is σ = 40347252. Its totient is φ = 39939312.

The previous prime is 40143277. The next prime is 40143287. The reversal of 40143281 is 18234104.

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 28718881 + 11424400 = 5359^2 + 3380^2 .

It is a cyclic number.

It is not a de Polignac number, because 40143281 - 2² = 40143277 is a prime.

It is a super-2 number, since 2×40143281² = 3222966018889922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40143287) by changing a digit.

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, 101690 + ... + 102083.

It is an arithmetic number, because the mean of its divisors is an integer number (10086813).

Almost surely, 2^40143281 is an apocalyptic number.

It is an amenable number.

40143281 is a deficient number, since it is larger than the sum of its proper divisors (203971).

40143281 is a wasteful number, since it uses less digits than its factorization.

40143281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 203970.

The product of its (nonzero) digits is 768, while the sum is 23.

The square root of 40143281 is about 6335.8725523798. The cubic root of 40143281 is about 342.4030478419.

Adding to 40143281 its reverse (18234104), we get a palindrome (58377385).

The spelling of 40143281 in words is "forty million, one hundred forty-three thousand, two hundred eighty-one".