20529520 has 80 divisors (see below), whose sum is σ = 53434080. Its totient is φ = 7270400.

The previous prime is 20529511. The next prime is 20529521. The reversal of 20529520 is 2592502.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×20529520² = 842922382860800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20529521) 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, 35796 + ... + 36364.

It is an arithmetic number, because the mean of its divisors is an integer number (667926).

Almost surely, 2^20529520 is an apocalyptic number.

20529520 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 20529520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26717040).

20529520 is an abundant number, since it is smaller than the sum of its proper divisors (32904560).

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

20529520 is a wasteful number, since it uses less digits than its factorization.

20529520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 634 (or 628 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 25.

The square root of 20529520 is about 4530.9513349847. The cubic root of 20529520 is about 273.8164896214.

It can be divided in two parts, 205 and 29520, that multiplied together give a square (6051600 = 2460²).

The spelling of 20529520 in words is "twenty million, five hundred twenty-nine thousand, five hundred twenty".