135315821 has 8 divisors (see below), whose sum is σ = 136435200. Its totient is φ = 134201232.

The previous prime is 135315809. The next prime is 135315839. The reversal of 135315821 is 128513531.

It is a happy number.

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 135315821 - 2⁶ = 135315757 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (135315841) 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, 73316 + ... + 75138.

It is an arithmetic number, because the mean of its divisors is an integer number (17054400).

Almost surely, 2^135315821 is an apocalyptic number.

It is an amenable number.

135315821 is a deficient number, since it is larger than the sum of its proper divisors (1119379).

135315821 is a wasteful number, since it uses less digits than its factorization.

135315821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2395.

The product of its digits is 3600, while the sum is 29.

The square root of 135315821 is about 11632.5328712194. The cubic root of 135315821 is about 513.3925067653.

The spelling of 135315821 in words is "one hundred thirty-five million, three hundred fifteen thousand, eight hundred twenty-one".