1616537226181 has 2 divisors, whose sum is σ = 1616537226182. Its totient is φ = 1616537226180.

The previous prime is 1616537226169. The next prime is 1616537226223. The reversal of 1616537226181 is 1816227356161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 883571800225 + 732965425956 = 939985^2 + 856134^2 .

It is a cyclic number.

It is not a de Polignac number, because 1616537226181 - 2⁷ = 1616537226053 is a prime.

It is a super-4 number, since 4×1616537226181⁴ (a number of 50 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1616537296181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 808268613090 + 808268613091.

It is an arithmetic number, because the mean of its divisors is an integer number (808268613091).

Almost surely, 2^{1616537226181} is an apocalyptic number.

It is an amenable number.

1616537226181 is a deficient number, since it is larger than the sum of its proper divisors (1).

1616537226181 is an equidigital number, since it uses as much as digits as its factorization.

1616537226181 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 725760, while the sum is 49.

The spelling of 1616537226181 in words is "one trillion, six hundred sixteen billion, five hundred thirty-seven million, two hundred twenty-six thousand, one hundred eighty-one".