19604521 has 2 divisors, whose sum is σ = 19604522. Its totient is φ = 19604520.

The previous prime is 19604513. The next prime is 19604531. The reversal of 19604521 is 12540691.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19536400 + 68121 = 4420^2 + 261^2 .

It is an emirp because it is prime and its reverse (12540691) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19604521 - 2³ = 19604513 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19604521.

It is not a weakly prime, because it can be changed into another prime (19604531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9802260 + 9802261.

It is an arithmetic number, because the mean of its divisors is an integer number (9802261).

Almost surely, 2^19604521 is an apocalyptic number.

It is an amenable number.

19604521 is a deficient number, since it is larger than the sum of its proper divisors (1).

19604521 is an equidigital number, since it uses as much as digits as its factorization.

19604521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 19604521 is about 4427.6992896989. The cubic root of 19604521 is about 269.6406788566.

The spelling of 19604521 in words is "nineteen million, six hundred four thousand, five hundred twenty-one".