20557221224 has 16 divisors (see below), whose sum is σ = 38559468420. Its totient is φ = 10274696320.

The previous prime is 20557221197. The next prime is 20557221263. The reversal of 20557221224 is 42212275502.

It can be written as a sum of positive squares in 2 ways, for example, as 20457580900 + 99640324 = 143030^2 + 9982^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 466907 + ... + 509034.

Almost surely, 2^20557221224 is an apocalyptic number.

It is an amenable number.

20557221224 is a deficient number, since it is larger than the sum of its proper divisors (18002247196).

20557221224 is a wasteful number, since it uses less digits than its factorization.

20557221224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 978580 (or 978576 counting only the distinct ones).

The product of its (nonzero) digits is 22400, while the sum is 32.

Adding to 20557221224 its reverse (42212275502), we get a palindrome (62769496726).

The spelling of 20557221224 in words is "twenty billion, five hundred fifty-seven million, two hundred twenty-one thousand, two hundred twenty-four".