135142721 has 8 divisors (see below), whose sum is σ = 154598400. Its totient is φ = 115724448.

The previous prime is 135142703. The next prime is 135142769. The reversal of 135142721 is 127241531.

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

It is not a de Polignac number, because 135142721 - 2¹⁰ = 135141697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (135142771) 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, 1121 + ... + 16478.

It is an arithmetic number, because the mean of its divisors is an integer number (19324800).

Almost surely, 2^135142721 is an apocalyptic number.

It is an amenable number.

135142721 is a deficient number, since it is larger than the sum of its proper divisors (19455679).

135142721 is a wasteful number, since it uses less digits than its factorization.

135142721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18703.

The product of its digits is 1680, while the sum is 26.

The square root of 135142721 is about 11625.0901501881. The cubic root of 135142721 is about 513.1734977253.

The spelling of 135142721 in words is "one hundred thirty-five million, one hundred forty-two thousand, seven hundred twenty-one".