20447520 has 96 divisors (see below), whose sum is σ = 66044160. Its totient is φ = 5314560.

The previous prime is 20447513. The next prime is 20447521. The reversal of 20447520 is 2574402.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is not an unprimeable number, because it can be changed into a prime (20447521) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19161 + ... + 20199.

It is an arithmetic number, because the mean of its divisors is an integer number (687960).

Almost surely, 2^20447520 is an apocalyptic number.

20447520 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 20447520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33022080).

20447520 is an abundant number, since it is smaller than the sum of its proper divisors (45596640).

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

20447520 is a wasteful number, since it uses less digits than its factorization.

20447520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1098 (or 1090 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 24.

The square root of 20447520 is about 4521.8934087393. The cubic root of 20447520 is about 273.4514394744.

The spelling of 20447520 in words is "twenty million, four hundred forty-seven thousand, five hundred twenty".