20117105626521 has 4 divisors (see below), whose sum is σ = 26822807502032. Its totient is φ = 13411403751012.

The previous prime is 20117105626511. The next prime is 20117105626531. The reversal of 20117105626521 is 12562650171102.

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 an interprime number because it is at equal distance from previous prime (20117105626511) and next prime (20117105626531).

It is not a de Polignac number, because 20117105626521 - 2⁵ = 20117105626489 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 20117105626521.

It is not an unprimeable number, because it can be changed into a prime (20117105626511) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3352850937751 + ... + 3352850937756.

It is an arithmetic number, because the mean of its divisors is an integer number (6705701875508).

Almost surely, 2^{20117105626521} is an apocalyptic number.

It is an amenable number.

20117105626521 is a deficient number, since it is larger than the sum of its proper divisors (6705701875511).

20117105626521 is an equidigital number, since it uses as much as digits as its factorization.

20117105626521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6705701875510.

The product of its (nonzero) digits is 50400, while the sum is 39.

Adding to 20117105626521 its reverse (12562650171102), we get a palindrome (32679755797623).

The spelling of 20117105626521 in words is "twenty trillion, one hundred seventeen billion, one hundred five million, six hundred twenty-six thousand, five hundred twenty-one".