20121326687135 has 16 divisors (see below), whose sum is σ = 25196155496640. Its totient is φ = 15396727653120.

The previous prime is 20121326687101. The next prime is 20121326687191. The reversal of 20121326687135 is 53178662312102.

It is not a de Polignac number, because 20121326687135 - 2⁶ = 20121326687071 is a prime.

It is a super-2 number, since 2×20121326687135² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20121326687135.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1256651 + ... + 6466979.

It is an arithmetic number, because the mean of its divisors is an integer number (1574759718540).

Almost surely, 2^{20121326687135} is an apocalyptic number.

20121326687135 is a deficient number, since it is larger than the sum of its proper divisors (5074828809505).

20121326687135 is a wasteful number, since it uses less digits than its factorization.

20121326687135 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5243938.

The product of its (nonzero) digits is 725760, while the sum is 47.

Adding to 20121326687135 its reverse (53178662312102), we get a palindrome (73299988999237).

The spelling of 20121326687135 in words is "twenty trillion, one hundred twenty-one billion, three hundred twenty-six million, six hundred eighty-seven thousand, one hundred thirty-five".