161616997 has 2 divisors, whose sum is σ = 161616998. Its totient is φ = 161616996.

The previous prime is 161616947. The next prime is 161617003. The reversal of 161616997 is 799616161.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 137499076 + 24117921 = 11726^2 + 4911^2 .

It is a cyclic number.

It is not a de Polignac number, because 161616997 - 2¹¹ = 161614949 is a prime.

It is a super-3 number, since 3×161616997³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161616947) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80808498 + 80808499.

It is an arithmetic number, because the mean of its divisors is an integer number (80808499).

Almost surely, 2^161616997 is an apocalyptic number.

It is an amenable number.

161616997 is a deficient number, since it is larger than the sum of its proper divisors (1).

161616997 is an equidigital number, since it uses as much as digits as its factorization.

161616997 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 122472, while the sum is 46.

The square root of 161616997 is about 12712.8673791557. The cubic root of 161616997 is about 544.7062322764.

The spelling of 161616997 in words is "one hundred sixty-one million, six hundred sixteen thousand, nine hundred ninety-seven".