166011561449 has 2 divisors, whose sum is σ = 166011561450. Its totient is φ = 166011561448.

The previous prime is 166011561437. The next prime is 166011561511. The reversal of 166011561449 is 944165110661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 135424000000 + 30587561449 = 368000^2 + 174893^2 .

It is a cyclic number.

It is not a de Polignac number, because 166011561449 - 2³⁶ = 97292084713 is a prime.

It is not a weakly prime, because it can be changed into another prime (166011561049) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83005780724 + 83005780725.

It is an arithmetic number, because the mean of its divisors is an integer number (83005780725).

Almost surely, 2^166011561449 is an apocalyptic number.

It is an amenable number.

166011561449 is a deficient number, since it is larger than the sum of its proper divisors (1).

166011561449 is an equidigital number, since it uses as much as digits as its factorization.

166011561449 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 155520, while the sum is 44.

The spelling of 166011561449 in words is "one hundred sixty-six billion, eleven million, five hundred sixty-one thousand, four hundred forty-nine".