161663041537913 has 2 divisors, whose sum is σ = 161663041537914. Its totient is φ = 161663041537912.

The previous prime is 161663041537901. The next prime is 161663041537927. The reversal of 161663041537913 is 319735140366161.

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., 88184063265769 + 73478978272144 = 9390637^2 + 8571988^2 .

It is a cyclic number.

It is not a de Polignac number, because 161663041537913 - 2²⁶ = 161662974429049 is a prime.

It is a super-2 number, since 2×161663041537913² (a number of 29 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (161663041537513) 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, 80831520768956 + 80831520768957.

It is an arithmetic number, because the mean of its divisors is an integer number (80831520768957).

Almost surely, 2^{161663041537913} is an apocalyptic number.

It is an amenable number.

161663041537913 is a deficient number, since it is larger than the sum of its proper divisors (1).

161663041537913 is an equidigital number, since it uses as much as digits as its factorization.

161663041537913 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7348320, while the sum is 56.

The spelling of 161663041537913 in words is "one hundred sixty-one trillion, six hundred sixty-three billion, forty-one million, five hundred thirty-seven thousand, nine hundred thirteen".