135621601755421 has 8 divisors (see below), whose sum is σ = 142759822707200. Its totient is φ = 128483404994880.

The previous prime is 135621601755413. The next prime is 135621601755439. The reversal of 135621601755421 is 124557106126531.

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 135621601755421 - 2³ = 135621601755413 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 (135621601755481) 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, 6083716 + ... + 17557186.

It is an arithmetic number, because the mean of its divisors is an integer number (17844977838400).

Almost surely, 2^{135621601755421} is an apocalyptic number.

It is an amenable number.

135621601755421 is a deficient number, since it is larger than the sum of its proper divisors (7138220951779).

135621601755421 is a wasteful number, since it uses less digits than its factorization.

135621601755421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12095619.

The product of its (nonzero) digits is 1512000, while the sum is 49.

The spelling of 135621601755421 in words is "one hundred thirty-five trillion, six hundred twenty-one billion, six hundred one million, seven hundred fifty-five thousand, four hundred twenty-one".