16451377361561 has 2 divisors, whose sum is σ = 16451377361562. Its totient is φ = 16451377361560.

The previous prime is 16451377361521. The next prime is 16451377361569. The reversal of 16451377361561 is 16516377315461.

16451377361561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10341241008400 + 6110136353161 = 3215780^2 + 2471869^2 .

It is a cyclic number.

It is not a de Polignac number, because 16451377361561 - 2¹⁴ = 16451377345177 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 16451377361497 and 16451377361506.

It is not a weakly prime, because it can be changed into another prime (16451377361569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8225688680780 + 8225688680781.

It is an arithmetic number, because the mean of its divisors is an integer number (8225688680781).

Almost surely, 2^{16451377361561} is an apocalyptic number.

It is an amenable number.

16451377361561 is a deficient number, since it is larger than the sum of its proper divisors (1).

16451377361561 is an equidigital number, since it uses as much as digits as its factorization.

16451377361561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9525600, while the sum is 56.

The spelling of 16451377361561 in words is "sixteen trillion, four hundred fifty-one billion, three hundred seventy-seven million, three hundred sixty-one thousand, five hundred sixty-one".