161816801 has 2 divisors, whose sum is σ = 161816802. Its totient is φ = 161816800.

The previous prime is 161816789. The next prime is 161816861. The reversal of 161816801 is 108618161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 133980625 + 27836176 = 11575^2 + 5276^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161816801 is a prime.

It is a Chen prime.

It is equal to p_9070574 and since 161816801 and 9070574 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (161816861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80908400 + 80908401.

It is an arithmetic number, because the mean of its divisors is an integer number (80908401).

Almost surely, 2^161816801 is an apocalyptic number.

It is an amenable number.

161816801 is a deficient number, since it is larger than the sum of its proper divisors (1).

161816801 is an equidigital number, since it uses as much as digits as its factorization.

161816801 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2304, while the sum is 32.

The square root of 161816801 is about 12720.7232891845. The cubic root of 161816801 is about 544.9306098003.

The spelling of 161816801 in words is "one hundred sixty-one million, eight hundred sixteen thousand, eight hundred one".