19136561 has 2 divisors, whose sum is σ = 19136562. Its totient is φ = 19136560.

The previous prime is 19136539. The next prime is 19136569. The reversal of 19136561 is 16563191.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19088161 + 48400 = 4369^2 + 220^2 .

It is a cyclic number.

It is not a de Polignac number, because 19136561 - 2⁶ = 19136497 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (19136569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9568280 + 9568281.

It is an arithmetic number, because the mean of its divisors is an integer number (9568281).

Almost surely, 2^19136561 is an apocalyptic number.

It is an amenable number.

19136561 is a deficient number, since it is larger than the sum of its proper divisors (1).

19136561 is an equidigital number, since it uses as much as digits as its factorization.

19136561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4860, while the sum is 32.

The square root of 19136561 is about 4374.5355182008. The cubic root of 19136561 is about 267.4779368649.

The spelling of 19136561 in words is "nineteen million, one hundred thirty-six thousand, five hundred sixty-one".