20820750 has 128 divisors (see below), whose sum is σ = 58226688. Its totient is φ = 4928000.

The previous prime is 20820731. The next prime is 20820757. The reversal of 20820750 is 5702802.

It is a self number, because there is not a number n which added to its sum of digits gives 20820750.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20820757) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 293215 + ... + 293285.

It is an arithmetic number, because the mean of its divisors is an integer number (454896).

Almost surely, 2^20820750 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20820750, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29113344).

20820750 is an abundant number, since it is smaller than the sum of its proper divisors (37405938).

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

20820750 is a wasteful number, since it uses less digits than its factorization.

20820750 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131 (or 121 counting only the distinct ones).

The product of its (nonzero) digits is 1120, while the sum is 24.

The square root of 20820750 is about 4562.9760025667. The cubic root of 20820750 is about 275.1051939155.

The spelling of 20820750 in words is "twenty million, eight hundred twenty thousand, seven hundred fifty".