409039918561 has 2 divisors, whose sum is σ = 409039918562. Its totient is φ = 409039918560.

The previous prime is 409039918531. The next prime is 409039918579. The reversal of 409039918561 is 165819930904.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 296895304161 + 112144614400 = 544881^2 + 334880^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-409039918561 is a prime.

It is not a weakly prime, because it can be changed into another prime (409039918531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 204519959280 + 204519959281.

It is an arithmetic number, because the mean of its divisors is an integer number (204519959281).

Almost surely, 2^409039918561 is an apocalyptic number.

It is an amenable number.

409039918561 is a deficient number, since it is larger than the sum of its proper divisors (1).

409039918561 is an equidigital number, since it uses as much as digits as its factorization.

409039918561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2099520, while the sum is 55.

The spelling of 409039918561 in words is "four hundred nine billion, thirty-nine million, nine hundred eighteen thousand, five hundred sixty-one".