161604893 has 2 divisors, whose sum is σ = 161604894. Its totient is φ = 161604892.

The previous prime is 161604889. The next prime is 161604929. The reversal of 161604893 is 398406161.

161604893 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 112296409 + 49308484 = 10597^2 + 7022^2 .

It is a cyclic number.

It is not a de Polignac number, because 161604893 - 2² = 161604889 is a prime.

It is a super-2 number, since 2×161604893² = 52232282883082898, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161604853) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80802446 + 80802447.

It is an arithmetic number, because the mean of its divisors is an integer number (80802447).

Almost surely, 2^161604893 is an apocalyptic number.

It is an amenable number.

161604893 is a deficient number, since it is larger than the sum of its proper divisors (1).

161604893 is an equidigital number, since it uses as much as digits as its factorization.

161604893 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31104, while the sum is 38.

The square root of 161604893 is about 12712.3913171362. The cubic root of 161604893 is about 544.6926336885.

The spelling of 161604893 in words is "one hundred sixty-one million, six hundred four thousand, eight hundred ninety-three".