40807561 has 4 divisors (see below), whose sum is σ = 40820500. Its totient is φ = 40794624.

The previous prime is 40807549. The next prime is 40807567. The reversal of 40807561 is 16570804.

40807561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 11431161 + 29376400 = 3381^2 + 5420^2 .

It is a cyclic number.

It is not a de Polignac number, because 40807561 - 2⁷ = 40807433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40807567) 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 3 ways as a sum of consecutive naturals, for example, 1705 + ... + 9193.

It is an arithmetic number, because the mean of its divisors is an integer number (10205125).

Almost surely, 2^40807561 is an apocalyptic number.

It is an amenable number.

40807561 is a deficient number, since it is larger than the sum of its proper divisors (12939).

40807561 is an equidigital number, since it uses as much as digits as its factorization.

40807561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12938.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 40807561 is about 6388.0796018835. The cubic root of 40807561 is about 344.2813887696.

The spelling of 40807561 in words is "forty million, eight hundred seven thousand, five hundred sixty-one".