135603721 has 8 divisors (see below), whose sum is σ = 148083264. Its totient is φ = 123149520.

The previous prime is 135603701. The next prime is 135603751. The reversal of 135603721 is 127306531.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 135603721 - 2⁷ = 135603593 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 135603721.

It is not an unprimeable number, because it can be changed into a prime (135603701) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5895 + ... + 17491.

It is an arithmetic number, because the mean of its divisors is an integer number (18510408).

Almost surely, 2^135603721 is an apocalyptic number.

135603721 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

135603721 is a deficient number, since it is larger than the sum of its proper divisors (12479543).

135603721 is a wasteful number, since it uses less digits than its factorization.

135603721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12671.

The product of its (nonzero) digits is 3780, while the sum is 28.

The square root of 135603721 is about 11644.9010730019. The cubic root of 135603721 is about 513.7563494182.

The spelling of 135603721 in words is "one hundred thirty-five million, six hundred three thousand, seven hundred twenty-one".