20825540 has 48 divisors (see below), whose sum is σ = 45405360. Its totient is φ = 8017920.

The previous prime is 20825503. The next prime is 20825551. The reversal of 20825540 is 4552802.

It can be written as a sum of positive squares in 8 ways, for example, as 3319684 + 17505856 = 1822^2 + 4184^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 89264 + ... + 89496.

It is an arithmetic number, because the mean of its divisors is an integer number (945945).

Almost surely, 2^20825540 is an apocalyptic number.

20825540 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 20825540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22702680).

20825540 is an abundant number, since it is smaller than the sum of its proper divisors (24579820).

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

20825540 is a wasteful number, since it uses less digits than its factorization.

20825540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392 (or 390 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 26.

The square root of 20825540 is about 4563.5008491289. The cubic root of 20825540 is about 275.1262891024.

The spelling of 20825540 in words is "twenty million, eight hundred twenty-five thousand, five hundred forty".