16851121543 has 2 divisors, whose sum is σ = 16851121544. Its totient is φ = 16851121542.

The previous prime is 16851121523. The next prime is 16851121561. The reversal of 16851121543 is 34512115861.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 16851121543 - 2²¹ = 16849024391 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16851121523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8425560771 + 8425560772.

It is an arithmetic number, because the mean of its divisors is an integer number (8425560772).

Almost surely, 2^16851121543 is an apocalyptic number.

16851121543 is a deficient number, since it is larger than the sum of its proper divisors (1).

16851121543 is an equidigital number, since it uses as much as digits as its factorization.

16851121543 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 28800, while the sum is 37.

The spelling of 16851121543 in words is "sixteen billion, eight hundred fifty-one million, one hundred twenty-one thousand, five hundred forty-three".