16555606181 has 2 divisors, whose sum is σ = 16555606182. Its totient is φ = 16555606180.

The previous prime is 16555606153. The next prime is 16555606187. The reversal of 16555606181 is 18160655561.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16343321281 + 212284900 = 127841^2 + 14570^2 .

It is a cyclic number.

It is not a de Polignac number, because 16555606181 - 2¹⁴ = 16555589797 is a prime.

It is a super-2 number, since 2×16555606181² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16555606187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8277803090 + 8277803091.

It is an arithmetic number, because the mean of its divisors is an integer number (8277803091).

Almost surely, 2^16555606181 is an apocalyptic number.

It is an amenable number.

16555606181 is a deficient number, since it is larger than the sum of its proper divisors (1).

16555606181 is an equidigital number, since it uses as much as digits as its factorization.

16555606181 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216000, while the sum is 44.

The spelling of 16555606181 in words is "sixteen billion, five hundred fifty-five million, six hundred six thousand, one hundred eighty-one".