161855297792933 has 2 divisors, whose sum is σ = 161855297792934. Its totient is φ = 161855297792932.

The previous prime is 161855297792887. The next prime is 161855297792971. The reversal of 161855297792933 is 339297792558161.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 144843319097569 + 17011978695364 = 12035087^2 + 4124558^2 .

It is a cyclic number.

It is not a de Polignac number, because 161855297792933 - 2¹⁶ = 161855297727397 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161855297792033) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80927648896466 + 80927648896467.

It is an arithmetic number, because the mean of its divisors is an integer number (80927648896467).

Almost surely, 2^{161855297792933} is an apocalyptic number.

It is an amenable number.

161855297792933 is a deficient number, since it is larger than the sum of its proper divisors (1).

161855297792933 is an equidigital number, since it uses as much as digits as its factorization.

161855297792933 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1543147200, while the sum is 77.

The spelling of 161855297792933 in words is "one hundred sixty-one trillion, eight hundred fifty-five billion, two hundred ninety-seven million, seven hundred ninety-two thousand, nine hundred thirty-three".