20511121205 has 8 divisors (see below), whose sum is σ = 25908784800. Its totient is φ = 15545270736.

The previous prime is 20511121193. The next prime is 20511121219. The reversal of 20511121205 is 50212111502.

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

It is not a de Polignac number, because 20511121205 - 2¹⁰ = 20511120181 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 107953175 + ... + 107953364.

It is an arithmetic number, because the mean of its divisors is an integer number (3238598100).

Almost surely, 2^20511121205 is an apocalyptic number.

It is an amenable number.

20511121205 is a deficient number, since it is larger than the sum of its proper divisors (5397663595).

20511121205 is a wasteful number, since it uses less digits than its factorization.

20511121205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215906563.

The product of its (nonzero) digits is 200, while the sum is 20.

Adding to 20511121205 its reverse (50212111502), we get a palindrome (70723232707).

The spelling of 20511121205 in words is "twenty billion, five hundred eleven million, one hundred twenty-one thousand, two hundred five".