861120252172225 has 24 divisors (see below), whose sum is σ = 1069220272275000. Its totient is φ = 687973050263040.

The previous prime is 861120252172217. The next prime is 861120252172259. The reversal of 861120252172225 is 522271252021168.

It is a happy number.

It can be written as a sum of positive squares in 12 ways, for example, as 63525108229696 + 797595143942529 = 7970264^2 + 28241727^2 .

It is not a de Polignac number, because 861120252172225 - 2³ = 861120252172217 is a prime.

It is a super-2 number, since 2×861120252172225² (a number of 31 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 192535651 + ... + 196957399.

It is an arithmetic number, because the mean of its divisors is an integer number (44550844678125).

Almost surely, 2^{861120252172225} is an apocalyptic number.

It is an amenable number.

861120252172225 is a deficient number, since it is larger than the sum of its proper divisors (208100020102775).

861120252172225 is a wasteful number, since it uses less digits than its factorization.

861120252172225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4432197 (or 4432192 counting only the distinct ones).

The product of its (nonzero) digits is 537600, while the sum is 46.

The spelling of 861120252172225 in words is "eight hundred sixty-one trillion, one hundred twenty billion, two hundred fifty-two million, one hundred seventy-two thousand, two hundred twenty-five".