40013081 has 2 divisors, whose sum is σ = 40013082. Its totient is φ = 40013080.

The previous prime is 40013041. The next prime is 40013093. The reversal of 40013081 is 18031004.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21307456 + 18705625 = 4616^2 + 4325^2 .

It is a cyclic number.

It is not a de Polignac number, because 40013081 - 2²² = 35818777 is a prime.

It is a super-2 number, since 2×40013081² = 3202093302225122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (40013041) 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 as a sum of consecutive naturals, namely, 20006540 + 20006541.

It is an arithmetic number, because the mean of its divisors is an integer number (20006541).

Almost surely, 2^40013081 is an apocalyptic number.

It is an amenable number.

40013081 is a deficient number, since it is larger than the sum of its proper divisors (1).

40013081 is an equidigital number, since it uses as much as digits as its factorization.

40013081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 40013081 is about 6325.5893796547. The cubic root of 40013081 is about 342.0324655978.

Adding to 40013081 its reverse (18031004), we get a palindrome (58044085).

The spelling of 40013081 in words is "forty million, thirteen thousand, eighty-one".