20525280 has 96 divisors (see below), whose sum is σ = 65808288. Its totient is φ = 5376000.

The previous prime is 20525261. The next prime is 20525287. The reversal of 20525280 is 8252502.

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 a self number, because there is not a number n which added to its sum of digits gives 20525280.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20525287) 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, 28930 + ... + 29630.

It is an arithmetic number, because the mean of its divisors is an integer number (685503).

Almost surely, 2^20525280 is an apocalyptic number.

20525280 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 20525280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32904144).

20525280 is an abundant number, since it is smaller than the sum of its proper divisors (45283008).

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

20525280 is a wasteful number, since it uses less digits than its factorization.

20525280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 780 (or 772 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 24.

The square root of 20525280 is about 4530.4834179147. The cubic root of 20525280 is about 273.7976377137.

Adding to 20525280 its reverse (8252502), we get a palindrome (28777782).

The spelling of 20525280 in words is "twenty million, five hundred twenty-five thousand, two hundred eighty".