16551537917 has 2 divisors, whose sum is σ = 16551537918. Its totient is φ = 16551537916.

The previous prime is 16551537881. The next prime is 16551537973. The reversal of 16551537917 is 71973515561.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11842010041 + 4709527876 = 108821^2 + 68626^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16551537917 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16551537617) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8275768958 + 8275768959.

It is an arithmetic number, because the mean of its divisors is an integer number (8275768959).

Almost surely, 2^16551537917 is an apocalyptic number.

It is an amenable number.

16551537917 is a deficient number, since it is larger than the sum of its proper divisors (1).

16551537917 is an equidigital number, since it uses as much as digits as its factorization.

16551537917 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 992250, while the sum is 50.

The spelling of 16551537917 in words is "sixteen billion, five hundred fifty-one million, five hundred thirty-seven thousand, nine hundred seventeen".