135647621 has 2 divisors, whose sum is σ = 135647622. Its totient is φ = 135647620.

The previous prime is 135647581. The next prime is 135647623. The reversal of 135647621 is 126746531.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 108451396 + 27196225 = 10414^2 + 5215^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-135647621 is a prime.

Together with 135647623, 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 (135647623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 67823810 + 67823811.

It is an arithmetic number, because the mean of its divisors is an integer number (67823811).

Almost surely, 2^135647621 is an apocalyptic number.

It is an amenable number.

135647621 is a deficient number, since it is larger than the sum of its proper divisors (1).

135647621 is an equidigital number, since it uses as much as digits as its factorization.

135647621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 30240, while the sum is 35.

The square root of 135647621 is about 11646.7858656369. The cubic root of 135647621 is about 513.8117841565.

The spelling of 135647621 in words is "one hundred thirty-five million, six hundred forty-seven thousand, six hundred twenty-one".