136956221 has 2 divisors, whose sum is σ = 136956222. Its totient is φ = 136956220.

The previous prime is 136956151. The next prime is 136956223. The reversal of 136956221 is 122659631.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 105472900 + 31483321 = 10270^2 + 5611^2 .

It is a cyclic number.

It is not a de Polignac number, because 136956221 - 2¹⁴ = 136939837 is a prime.

Together with 136956223, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (136956223) 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, 68478110 + 68478111.

It is an arithmetic number, because the mean of its divisors is an integer number (68478111).

Almost surely, 2^136956221 is an apocalyptic number.

It is an amenable number.

136956221 is a deficient number, since it is larger than the sum of its proper divisors (1).

136956221 is an equidigital number, since it uses as much as digits as its factorization.

136956221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 19440, while the sum is 35.

The square root of 136956221 is about 11702.8296150974. The cubic root of 136956221 is about 515.4587560840.

The spelling of 136956221 in words is "one hundred thirty-six million, nine hundred fifty-six thousand, two hundred twenty-one".