20563520 has 56 divisors (see below), whose sum is σ = 49377600. Its totient is φ = 8156672.

The previous prime is 20563519. The next prime is 20563537. The reversal of 20563520 is 2536502.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 57101 + ... + 57459.

Almost surely, 2^20563520 is an apocalyptic number.

20563520 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 20563520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24688800).

20563520 is an abundant number, since it is smaller than the sum of its proper divisors (28814080).

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

20563520 is a wasteful number, since it uses less digits than its factorization.

20563520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 555 (or 545 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 23.

The square root of 20563520 is about 4534.7017542502. The cubic root of 20563520 is about 273.9675668006.

The spelling of 20563520 in words is "twenty million, five hundred sixty-three thousand, five hundred twenty".