135242121 has 16 divisors (see below), whose sum is σ = 206668800. Its totient is φ = 77061648.

The previous prime is 135242117. The next prime is 135242137. The reversal of 135242121 is 121242531.

It is not a de Polignac number, because 135242121 - 2² = 135242117 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (135242161) 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 in 15 ways as a sum of consecutive naturals, for example, 1431 + ... + 16508.

It is an arithmetic number, because the mean of its divisors is an integer number (12916800).

Almost surely, 2^135242121 is an apocalyptic number.

It is an amenable number.

135242121 is a deficient number, since it is larger than the sum of its proper divisors (71426679).

135242121 is a wasteful number, since it uses less digits than its factorization.

135242121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18308.

The product of its digits is 480, while the sum is 21.

The square root of 135242121 is about 11629.3646000115. The cubic root of 135242121 is about 513.2992831278.

Adding to 135242121 its reverse (121242531), we get a palindrome (256484652).

The spelling of 135242121 in words is "one hundred thirty-five million, two hundred forty-two thousand, one hundred twenty-one".