135715510607621 has 4 divisors (see below), whose sum is σ = 155103440694432. Its totient is φ = 116327580520812.

The previous prime is 135715510607581. The next prime is 135715510607639. The reversal of 135715510607621 is 126706015517531.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-135715510607621 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 135715510607621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (135715510607821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9693965043395 + ... + 9693965043408.

It is an arithmetic number, because the mean of its divisors is an integer number (38775860173608).

Almost surely, 2^{135715510607621} is an apocalyptic number.

It is an amenable number.

135715510607621 is a deficient number, since it is larger than the sum of its proper divisors (19387930086811).

135715510607621 is an equidigital number, since it uses as much as digits as its factorization.

135715510607621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19387930086810.

The product of its (nonzero) digits is 1323000, while the sum is 50.

The spelling of 135715510607621 in words is "one hundred thirty-five trillion, seven hundred fifteen billion, five hundred ten million, six hundred seven thousand, six hundred twenty-one".