20557221226 has 4 divisors (see below), whose sum is σ = 30835831842. Its totient is φ = 10278610612.

The previous prime is 20557221197. The next prime is 20557221263. The reversal of 20557221226 is 62212275502.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 10701695601 + 9855525625 = 103449^2 + 99275^2 .

It is a junction number, because it is equal to n+sod(n) for n = 20557221191 and 20557221200.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 5139305305 + ... + 5139305308.

Almost surely, 2^20557221226 is an apocalyptic number.

20557221226 is a deficient number, since it is larger than the sum of its proper divisors (10278610616).

20557221226 is a wasteful number, since it uses less digits than its factorization.

20557221226 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10278610615.

The product of its (nonzero) digits is 33600, while the sum is 34.

Adding to 20557221226 its reverse (62212275502), we get a palindrome (82769496728).

The spelling of 20557221226 in words is "twenty billion, five hundred fifty-seven million, two hundred twenty-one thousand, two hundred twenty-six".