40106581 has 2 divisors, whose sum is σ = 40106582. Its totient is φ = 40106580.

The previous prime is 40106579. The next prime is 40106597. The reversal of 40106581 is 18560104.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 37625956 + 2480625 = 6134^2 + 1575^2 .

It is a cyclic number.

It is not a de Polignac number, because 40106581 - 2¹ = 40106579 is a prime.

It is a super-2 number, since 2×40106581² = 3217075679019122, which contains 22 as substring.

Together with 40106579, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40106501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20053290 + 20053291.

It is an arithmetic number, because the mean of its divisors is an integer number (20053291).

Almost surely, 2^40106581 is an apocalyptic number.

It is an amenable number.

40106581 is a deficient number, since it is larger than the sum of its proper divisors (1).

40106581 is an equidigital number, since it uses as much as digits as its factorization.

40106581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 960, while the sum is 25.

The square root of 40106581 is about 6332.9756828840. The cubic root of 40106581 is about 342.2986715267.

Adding to 40106581 its reverse (18560104), we get a palindrome (58666685).

The spelling of 40106581 in words is "forty million, one hundred six thousand, five hundred eighty-one".