166616380069 has 2 divisors, whose sum is σ = 166616380070. Its totient is φ = 166616380068.

The previous prime is 166616380057. The next prime is 166616380121. The reversal of 166616380069 is 960083616661.

It is an a-pointer prime, because the next prime (166616380121) can be obtained adding 166616380069 to its sum of digits (52).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 166576627044 + 39753025 = 408138^2 + 6305^2 .

It is a cyclic number.

It is not a de Polignac number, because 166616380069 - 2¹⁵ = 166616347301 is a prime.

It is a super-2 number, since 2×166616380069² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 166616379998 and 166616380025.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166616380009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83308190034 + 83308190035.

It is an arithmetic number, because the mean of its divisors is an integer number (83308190035).

Almost surely, 2^166616380069 is an apocalyptic number.

It is an amenable number.

166616380069 is a deficient number, since it is larger than the sum of its proper divisors (1).

166616380069 is an equidigital number, since it uses as much as digits as its factorization.

166616380069 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1679616, while the sum is 52.

The spelling of 166616380069 in words is "one hundred sixty-six billion, six hundred sixteen million, three hundred eighty thousand, sixty-nine".