20557264 has 60 divisors (see below), whose sum is σ = 49921284. Its totient is φ = 8128512.

The previous prime is 20557241. The next prime is 20557279. The reversal of 20557264 is 46275502.

It can be written as a sum of positive squares in 2 ways, for example, as 10188864 + 10368400 = 3192^2 + 3220^2 .

It is a super-3 number, since 3×20557264³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9184 + ... + 11200.

Almost surely, 2^20557264 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20557264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24960642).

20557264 is an abundant number, since it is smaller than the sum of its proper divisors (29364020).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20557264 is a wasteful number, since it uses less digits than its factorization.

20557264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2052 (or 2039 counting only the distinct ones).

The product of its (nonzero) digits is 16800, while the sum is 31.

The square root of 20557264 is about 4534.0119099976. The cubic root of 20557264 is about 273.9397811080.

The spelling of 20557264 in words is "twenty million, five hundred fifty-seven thousand, two hundred sixty-four".