161645935949 has 2 divisors, whose sum is σ = 161645935950. Its totient is φ = 161645935948.

The previous prime is 161645935883. The next prime is 161645935967. The reversal of 161645935949 is 949539546161.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 161207871049 + 438064900 = 401507^2 + 20930^2 .

It is a cyclic number.

It is not a de Polignac number, because 161645935949 - 2¹⁶ = 161645870413 is a prime.

It is a super-2 number, since 2×161645935949² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 161645935891 and 161645935900.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161645935249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80822967974 + 80822967975.

It is an arithmetic number, because the mean of its divisors is an integer number (80822967975).

Almost surely, 2^161645935949 is an apocalyptic number.

It is an amenable number.

161645935949 is a deficient number, since it is larger than the sum of its proper divisors (1).

161645935949 is an equidigital number, since it uses as much as digits as its factorization.

161645935949 is an evil number, because the sum of its binary digits is even.

The product of its digits is 31492800, while the sum is 62.

The spelling of 161645935949 in words is "one hundred sixty-one billion, six hundred forty-five million, nine hundred thirty-five thousand, nine hundred forty-nine".