135352721 has 4 divisors (see below), whose sum is σ = 154688832. Its totient is φ = 116016612.

The previous prime is 135352709. The next prime is 135352739. The reversal of 135352721 is 127253531.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 127253531 = 131 ⋅971401.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-135352721 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (135351721) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9668045 + ... + 9668058.

It is an arithmetic number, because the mean of its divisors is an integer number (38672208).

Almost surely, 2^135352721 is an apocalyptic number.

It is an amenable number.

135352721 is a deficient number, since it is larger than the sum of its proper divisors (19336111).

135352721 is an equidigital number, since it uses as much as digits as its factorization.

135352721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19336110.

The product of its digits is 6300, while the sum is 29.

The square root of 135352721 is about 11634.1188321248. The cubic root of 135352721 is about 513.4391691133.

The spelling of 135352721 in words is "one hundred thirty-five million, three hundred fifty-two thousand, seven hundred twenty-one".