245105196561 has 15 divisors (see below), whose sum is σ = 366151456011. Its totient is φ = 163400493888.

The previous prime is 245105196559. The next prime is 245105196569. The reversal of 245105196561 is 165691501542.

The square root of 245105196561 is 495081.

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

245105196561 is a `hidden beast` number, since 2 + 4 + 5 + 10 + 519 + 65 + 61 = 666.

It can be written as a sum of positive squares in only one way, i.e., 194155678161 + 50949518400 = 440631^2 + 225720^2 .

It is not a de Polignac number, because 245105196561 - 2¹ = 245105196559 is a prime.

It is not an unprimeable number, because it can be changed into a prime (245105196569) by changing a digit.

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 14 ways as a sum of consecutive naturals, for example, 4428225 + ... + 4483233.

Almost surely, 2^245105196561 is an apocalyptic number.

245105196561 is the 495081-st square number.

245105196561 is the 247541-st centered octagonal number.

It is an amenable number.

245105196561 is a deficient number, since it is larger than the sum of its proper divisors (121046259450).

245105196561 is an frugal number, since it uses more digits than its factorization.

245105196561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110030 (or 55012 counting only the distinct ones).

The product of its (nonzero) digits is 324000, while the sum is 45.

The spelling of 245105196561 in words is "two hundred forty-five billion, one hundred five million, one hundred ninety-six thousand, five hundred sixty-one".