19804901 has 2 divisors, whose sum is σ = 19804902. Its totient is φ = 19804900.

The previous prime is 19804871. The next prime is 19804933. The reversal of 19804901 is 10940891.

It is an a-pointer prime, because the next prime (19804933) can be obtained adding 19804901 to its sum of digits (32).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19802500 + 2401 = 4450^2 + 49^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19804901 is a prime.

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 (19804991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9902450 + 9902451.

It is an arithmetic number, because the mean of its divisors is an integer number (9902451).

Almost surely, 2^19804901 is an apocalyptic number.

It is an amenable number.

19804901 is a deficient number, since it is larger than the sum of its proper divisors (1).

19804901 is an equidigital number, since it uses as much as digits as its factorization.

19804901 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592, while the sum is 32.

The square root of 19804901 is about 4450.2697671040. The cubic root of 19804901 is about 270.5562423839.

The spelling of 19804901 in words is "nineteen million, eight hundred four thousand, nine hundred one".