20520800 has 72 divisors (see below), whose sum is σ = 50762376. Its totient is φ = 8099840.

The previous prime is 20520769. The next prime is 20520809. The reversal of 20520800 is 802502.

It is a happy number.

It is a super-2 number, since 2×20520800² = 842206465280000, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20520809) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 90287 + ... + 90513.

It is an arithmetic number, because the mean of its divisors is an integer number (705033).

Almost surely, 2^20520800 is an apocalyptic number.

20520800 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 20520800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25381188).

20520800 is an abundant number, since it is smaller than the sum of its proper divisors (30241576).

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

20520800 is a wasteful number, since it uses less digits than its factorization.

20520800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 360 (or 347 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 17.

The square root of 20520800 is about 4529.9889624590. The cubic root of 20520800 is about 273.7777158958. Note that the first 4 decimals are identical.

The spelling of 20520800 in words is "twenty million, five hundred twenty thousand, eight hundred".