40247561 has 2 divisors, whose sum is σ = 40247562. Its totient is φ = 40247560.

The previous prime is 40247521. The next prime is 40247587. The reversal of 40247561 is 16574204.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 40246336 + 1225 = 6344^2 + 35^2 .

It is a cyclic number.

It is not a de Polignac number, because 40247561 - 2¹⁰ = 40246537 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (40247521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20123780 + 20123781.

It is an arithmetic number, because the mean of its divisors is an integer number (20123781).

Almost surely, 2^40247561 is an apocalyptic number.

It is an amenable number.

40247561 is a deficient number, since it is larger than the sum of its proper divisors (1).

40247561 is an equidigital number, since it uses as much as digits as its factorization.

40247561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6720, while the sum is 29.

The square root of 40247561 is about 6344.0965471846. The cubic root of 40247561 is about 342.6992777123.

The spelling of 40247561 in words is "forty million, two hundred forty-seven thousand, five hundred sixty-one".