20572928917 has 2 divisors, whose sum is σ = 20572928918. Its totient is φ = 20572928916.

The previous prime is 20572928861. The next prime is 20572928921. The reversal of 20572928917 is 71982927502.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16518932676 + 4053996241 = 128526^2 + 63671^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20572928917 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20572928977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10286464458 + 10286464459.

It is an arithmetic number, because the mean of its divisors is an integer number (10286464459).

Almost surely, 2^20572928917 is an apocalyptic number.

It is an amenable number.

20572928917 is a deficient number, since it is larger than the sum of its proper divisors (1).

20572928917 is an equidigital number, since it uses as much as digits as its factorization.

20572928917 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1270080, while the sum is 52.

The spelling of 20572928917 in words is "twenty billion, five hundred seventy-two million, nine hundred twenty-eight thousand, nine hundred seventeen".