19875642361 has 9 divisors (see below), whose sum is σ = 21116117901. Its totient is φ = 18704231232.

The previous prime is 19875642337. The next prime is 19875642389. The reversal of 19875642361 is 16324657891.

The square root of 19875642361 is 140981.

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

It can be written as a sum of positive squares in 4 ways, for example, as 281961 + 19875360400 = 531^2 + 140980^2 .

It is not a de Polignac number, because 19875642361 - 2¹¹ = 19875640313 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 19875642299 and 19875642308.

It is not an unprimeable number, because it can be changed into a prime (19875642301) 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 8 ways as a sum of consecutive naturals, for example, 2392531 + ... + 2400823.

Almost surely, 2^19875642361 is an apocalyptic number.

19875642361 is the 140981-st square number.

19875642361 is the 70491-st centered octagonal number.

It is an amenable number.

19875642361 is a deficient number, since it is larger than the sum of its proper divisors (1240475540).

19875642361 is an frugal number, since it uses more digits than its factorization.

19875642361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16620 (or 8310 counting only the distinct ones).

The product of its digits is 2177280, while the sum is 52.

The spelling of 19875642361 in words is "nineteen billion, eight hundred seventy-five million, six hundred forty-two thousand, three hundred sixty-one".