135517821 has 8 divisors (see below), whose sum is σ = 182445120. Its totient is φ = 89467872.

The previous prime is 135517813. The next prime is 135517843. The reversal of 135517821 is 128715531.

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

It is not a de Polignac number, because 135517821 - 2³ = 135517813 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (135517321) 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, 218976 + ... + 219593.

It is an arithmetic number, because the mean of its divisors is an integer number (22805640).

Almost surely, 2^135517821 is an apocalyptic number.

It is an amenable number.

135517821 is a deficient number, since it is larger than the sum of its proper divisors (46927299).

135517821 is a wasteful number, since it uses less digits than its factorization.

135517821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 438675.

The product of its digits is 8400, while the sum is 33.

The square root of 135517821 is about 11641.2121791504. The cubic root of 135517821 is about 513.6478445484.

The spelling of 135517821 in words is "one hundred thirty-five million, five hundred seventeen thousand, eight hundred twenty-one".