215839105409 has 2 divisors, whose sum is σ = 215839105410. Its totient is φ = 215839105408.

The previous prime is 215839105393. The next prime is 215839105477. The reversal of 215839105409 is 904501938512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 195837226225 + 20001879184 = 442535^2 + 141428^2 .

It is a cyclic number.

It is not a de Polignac number, because 215839105409 - 2⁴ = 215839105393 is a prime.

It is not a weakly prime, because it can be changed into another prime (215839107409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107919552704 + 107919552705.

It is an arithmetic number, because the mean of its divisors is an integer number (107919552705).

Almost surely, 2^215839105409 is an apocalyptic number.

It is an amenable number.

215839105409 is a deficient number, since it is larger than the sum of its proper divisors (1).

215839105409 is an equidigital number, since it uses as much as digits as its factorization.

215839105409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 388800, while the sum is 47.

The spelling of 215839105409 in words is "two hundred fifteen billion, eight hundred thirty-nine million, one hundred five thousand, four hundred nine".