161310673225 has 81 divisors (see below), whose sum is σ = 223948476927. Its totient is φ = 115208196480.

The previous prime is 161310673217. The next prime is 161310673229. The reversal of 161310673225 is 522376013161.

The square root of 161310673225 is 401635.

It is a perfect power (a square), and thus also a powerful number.

161310673225 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 13 ways, for example, as 93091501881 + 68219171344 = 305109^2 + 261188^2 .

It is not a de Polignac number, because 161310673225 - 2³ = 161310673217 is a prime.

It is a super-2 number, since 2×161310673225² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161310673229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 965932092 + ... + 965932258.

Almost surely, 2^161310673225 is an apocalyptic number.

161310673225 is the 401635-th square number.

161310673225 is the 200818-th centered octagonal number.

It is an amenable number.

161310673225 is a deficient number, since it is larger than the sum of its proper divisors (62637803702).

161310673225 is an equidigital number, since it uses as much as digits as its factorization.

161310673225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 444 (or 222 counting only the distinct ones).

The product of its (nonzero) digits is 45360, while the sum is 37.

Adding to 161310673225 its reverse (522376013161), we get a palindrome (683686686386).

The spelling of 161310673225 in words is "one hundred sixty-one billion, three hundred ten million, six hundred seventy-three thousand, two hundred twenty-five".