19790161 has 2 divisors, whose sum is σ = 19790162. Its totient is φ = 19790160.

The previous prime is 19790137. The next prime is 19790201. The reversal of 19790161 is 16109791.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15563025 + 4227136 = 3945^2 + 2056^2 .

It is an emirp because it is prime and its reverse (16109791) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19790161 - 2⁷ = 19790033 is a prime.

It is not a weakly prime, because it can be changed into another prime (19790101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9895080 + 9895081.

It is an arithmetic number, because the mean of its divisors is an integer number (9895081).

Almost surely, 2^19790161 is an apocalyptic number.

It is an amenable number.

19790161 is a deficient number, since it is larger than the sum of its proper divisors (1).

19790161 is an equidigital number, since it uses as much as digits as its factorization.

19790161 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3402, while the sum is 34.

The square root of 19790161 is about 4448.6133794701. The cubic root of 19790161 is about 270.4891043088.

The spelling of 19790161 in words is "nineteen million, seven hundred ninety thousand, one hundred sixty-one".