20007750 has 128 divisors (see below), whose sum is σ = 59185152. Its totient is φ = 4406400.

The previous prime is 20007749. The next prime is 20007773. The reversal of 20007750 is 5770002.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 194199 + ... + 194301.

It is an arithmetic number, because the mean of its divisors is an integer number (462384).

Almost surely, 2^20007750 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20007750, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29592576).

20007750 is an abundant number, since it is smaller than the sum of its proper divisors (39177402).

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

20007750 is a wasteful number, since it uses less digits than its factorization.

20007750 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167 (or 157 counting only the distinct ones).

The product of its (nonzero) digits is 490, while the sum is 21.

The square root of 20007750 is about 4473.0023474172. The cubic root of 20007750 is about 271.4768183593.

Subtracting from 20007750 its sum of digits (21), we obtain a square (20007729 = 4473²).

Adding to 20007750 its reverse (5770002), we get a palindrome (25777752).

The spelling of 20007750 in words is "twenty million, seven thousand, seven hundred fifty".