161559137 has 2 divisors, whose sum is σ = 161559138. Its totient is φ = 161559136.

The previous prime is 161559077. The next prime is 161559173. The reversal of 161559137 is 731955161.

Together with next prime (161559173) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 100781521 + 60777616 = 10039^2 + 7796^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161559137 is a prime.

It is a super-2 number, since 2×161559137² = 52202709496369538, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 161559137.

It is not a weakly prime, because it can be changed into another prime (161589137) 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, 80779568 + 80779569.

It is an arithmetic number, because the mean of its divisors is an integer number (80779569).

Almost surely, 2^161559137 is an apocalyptic number.

It is an amenable number.

161559137 is a deficient number, since it is larger than the sum of its proper divisors (1).

161559137 is an equidigital number, since it uses as much as digits as its factorization.

161559137 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 28350, while the sum is 38.

The square root of 161559137 is about 12710.5915283279. The cubic root of 161559137 is about 544.6412216546.

The spelling of 161559137 in words is "one hundred sixty-one million, five hundred fifty-nine thousand, one hundred thirty-seven".