161641730425 has 18 divisors (see below), whose sum is σ = 233159950878. Its totient is φ = 110840042880.

The previous prime is 161641730323. The next prime is 161641730441. The reversal of 161641730425 is 524037146161.

It can be written as a sum of positive squares in 3 ways, for example, as 22479904489 + 139161825936 = 149933^2 + 373044^2 .

It is not a de Polignac number, because 161641730425 - 2¹¹ = 161641728377 is a prime.

It is a super-2 number, since 2×161641730425² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 65974992 + ... + 65977441.

Almost surely, 2^161641730425 is an apocalyptic number.

It is an amenable number.

161641730425 is a deficient number, since it is larger than the sum of its proper divisors (71518220453).

161641730425 is a wasteful number, since it uses less digits than its factorization.

161641730425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131952457 (or 131952445 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 40.

Adding to 161641730425 its reverse (524037146161), we get a palindrome (685678876586).

The spelling of 161641730425 in words is "one hundred sixty-one billion, six hundred forty-one million, seven hundred thirty thousand, four hundred twenty-five".