23194443555721 has 3 divisors (see below), whose sum is σ = 23194448371783. Its totient is φ = 23194438739660.

The previous prime is 23194443555643. The next prime is 23194443555769. The reversal of 23194443555721 is 12755534449132.

The square root of 23194443555721 is 4816061.

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

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 743714787321 + 22450728768400 = 862389^2 + 4738220^2 .

It is not a de Polignac number, because 23194443555721 - 2⁷ = 23194443555593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (23194443565721) 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 2 ways as a sum of consecutive naturals, for example, 2408031 + ... + 7224091.

Almost surely, 2^{23194443555721} is an apocalyptic number.

23194443555721 is the 4816061-st square number.

23194443555721 is the 2408031-st centered octagonal number.

It is an amenable number.

23194443555721 is a deficient number, since it is larger than the sum of its proper divisors (4816062).

23194443555721 is an frugal number, since it uses more digits than its factorization.

23194443555721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9632122 (or 4816061 counting only the distinct ones).

The product of its digits is 18144000, while the sum is 55.

The spelling of 23194443555721 in words is "twenty-three trillion, one hundred ninety-four billion, four hundred forty-three million, five hundred fifty-five thousand, seven hundred twenty-one".