20556480 has 336 divisors, whose sum is σ = 83393280. Its totient is φ = 4257792.

The previous prime is 20556479. The next prime is 20556491. The reversal of 20556480 is 8465502.

It is a tau number, because it is divible by the number of its divisors (336).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 893749 + ... + 893771.

Almost surely, 2^20556480 is an apocalyptic number.

20556480 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20556480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41696640).

20556480 is an abundant number, since it is smaller than the sum of its proper divisors (62836800).

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

20556480 is a wasteful number, since it uses less digits than its factorization.

20556480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76 (or 59 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 30.

The square root of 20556480 is about 4533.9254515265. The cubic root of 20556480 is about 273.9362986160.

The spelling of 20556480 in words is "twenty million, five hundred fifty-six thousand, four hundred eighty".