40005261 has 6 divisors (see below), whose sum is σ = 57785390. Its totient is φ = 26670168.

The previous prime is 40005227. The next prime is 40005269. The reversal of 40005261 is 16250004.

It is a happy number.

40005261 is a `hidden beast` number, since 400 + 0 + 5 + 261 = 666.

40005261 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 30969225 + 9036036 = 5565^2 + 3006^2 .

It is not a de Polignac number, because 40005261 - 2⁶ = 40005197 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40005269) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2222506 + ... + 2222523.

Almost surely, 2^40005261 is an apocalyptic number.

It is an amenable number.

40005261 is a deficient number, since it is larger than the sum of its proper divisors (17780129).

40005261 is a wasteful number, since it uses less digits than its factorization.

40005261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4445035 (or 4445032 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 40005261 is about 6324.9712252310. The cubic root of 40005261 is about 342.0101823171.

Adding to 40005261 its reverse (16250004), we get a palindrome (56255265).

It can be divided in two parts, 4000 and 5261, that added together give a cube (9261 = 21³).

The spelling of 40005261 in words is "forty million, five thousand, two hundred sixty-one".