16551845857 has 2 divisors, whose sum is σ = 16551845858. Its totient is φ = 16551845856.

The previous prime is 16551845831. The next prime is 16551845911. The reversal of 16551845857 is 75854815561.

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., 12135445921 + 4416399936 = 110161^2 + 66456^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16551845857 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 16551845798 and 16551845807.

It is not a weakly prime, because it can be changed into another prime (16551848857) 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 as a sum of consecutive naturals, namely, 8275922928 + 8275922929.

It is an arithmetic number, because the mean of its divisors is an integer number (8275922929).

Almost surely, 2^16551845857 is an apocalyptic number.

It is an amenable number.

16551845857 is a deficient number, since it is larger than the sum of its proper divisors (1).

16551845857 is an equidigital number, since it uses as much as digits as its factorization.

16551845857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6720000, while the sum is 55.

The spelling of 16551845857 in words is "sixteen billion, five hundred fifty-one million, eight hundred forty-five thousand, eight hundred fifty-seven".