20205221511 has 8 divisors (see below), whose sum is σ = 26947853824. Its totient is φ = 13466368440.

The previous prime is 20205221489. The next prime is 20205221513. The reversal of 20205221511 is 11512250202.

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

It is not a de Polignac number, because 20205221511 - 2²² = 20201027207 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 (20205221513) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 932311 + ... + 953736.

It is an arithmetic number, because the mean of its divisors is an integer number (3368481728).

Almost surely, 2^20205221511 is an apocalyptic number.

20205221511 is a deficient number, since it is larger than the sum of its proper divisors (6742632313).

20205221511 is a wasteful number, since it uses less digits than its factorization.

20205221511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1889621.

The product of its (nonzero) digits is 400, while the sum is 21.

Adding to 20205221511 its reverse (11512250202), we get a palindrome (31717471713).

The spelling of 20205221511 in words is "twenty billion, two hundred five million, two hundred twenty-one thousand, five hundred eleven".