136406321 has 2 divisors, whose sum is σ = 136406322. Its totient is φ = 136406320.

The previous prime is 136406297. The next prime is 136406323. The reversal of 136406321 is 123604631.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 112042225 + 24364096 = 10585^2 + 4936^2 .

It is an emirp because it is prime and its reverse (123604631) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-136406321 is a prime.

Together with 136406323, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (136406323) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 68203160 + 68203161.

It is an arithmetic number, because the mean of its divisors is an integer number (68203161).

Almost surely, 2^136406321 is an apocalyptic number.

It is an amenable number.

136406321 is a deficient number, since it is larger than the sum of its proper divisors (1).

136406321 is an equidigital number, since it uses as much as digits as its factorization.

136406321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2592, while the sum is 26.

The square root of 136406321 is about 11679.3116663612. The cubic root of 136406321 is about 514.7679489966.

The spelling of 136406321 in words is "one hundred thirty-six million, four hundred six thousand, three hundred twenty-one".