20815200 has 324 divisors, whose sum is σ = 86830380. Its totient is φ = 4677120.

The previous prime is 20815169. The next prime is 20815211. The reversal of 20815200 is 251802.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

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 53 ways as a sum of consecutive naturals, for example, 352771 + ... + 352829.

It is an arithmetic number, because the mean of its divisors is an integer number (267995).

Almost surely, 2^20815200 is an apocalyptic number.

20815200 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 20815200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43415190).

20815200 is an abundant number, since it is smaller than the sum of its proper divisors (66015180).

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

20815200 is a wasteful number, since it uses less digits than its factorization.

20815200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99 (or 76 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

The square root of 20815200 is about 4562.3678063041. The cubic root of 20815200 is about 275.0807476378.

The spelling of 20815200 in words is "twenty million, eight hundred fifteen thousand, two hundred".