20750730 has 128 divisors (see below), whose sum is σ = 66963456. Its totient is φ = 3974400.

The previous prime is 20750701. The next prime is 20750767. The reversal of 20750730 is 3705702.

It is a self number, because there is not a number n which added to its sum of digits gives 20750730.

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, 29685 + ... + 30375.

It is an arithmetic number, because the mean of its divisors is an integer number (523152).

Almost surely, 2^20750730 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20750730, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33481728).

20750730 is an abundant number, since it is smaller than the sum of its proper divisors (46212726).

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

20750730 is a wasteful number, since it uses less digits than its factorization.

20750730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 732.

The product of its (nonzero) digits is 1470, while the sum is 24.

The square root of 20750730 is about 4555.2969167772. The cubic root of 20750730 is about 274.7964554418.

The spelling of 20750730 in words is "twenty million, seven hundred fifty thousand, seven hundred thirty".