16355445311561 has 2 divisors, whose sum is σ = 16355445311562. Its totient is φ = 16355445311560.

The previous prime is 16355445311549. The next prime is 16355445311587. The reversal of 16355445311561 is 16511354455361.

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., 16330739759161 + 24705552400 = 4041131^2 + 157180^2 .

It is a cyclic number.

It is not a de Polignac number, because 16355445311561 - 2¹⁴ = 16355445295177 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (16355445011561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8177722655780 + 8177722655781.

It is an arithmetic number, because the mean of its divisors is an integer number (8177722655781).

Almost surely, 2^{16355445311561} is an apocalyptic number.

It is an amenable number.

16355445311561 is a deficient number, since it is larger than the sum of its proper divisors (1).

16355445311561 is an equidigital number, since it uses as much as digits as its factorization.

16355445311561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3240000, while the sum is 50.

The spelling of 16355445311561 in words is "sixteen trillion, three hundred fifty-five billion, four hundred forty-five million, three hundred eleven thousand, five hundred sixty-one".