20751066 has 80 divisors (see below), whose sum is σ = 55059840. Its totient is φ = 5715360.

The previous prime is 20751061. The next prime is 20751077. The reversal of 20751066 is 66015702.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20751061) by changing a digit.

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 39 ways as a sum of consecutive naturals, for example, 32571 + ... + 33201.

It is an arithmetic number, because the mean of its divisors is an integer number (688248).

Almost surely, 2^20751066 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20751066, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27529920).

20751066 is an abundant number, since it is smaller than the sum of its proper divisors (34308774).

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

20751066 is a wasteful number, since it uses less digits than its factorization.

20751066 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 681 (or 672 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 27.

The square root of 20751066 is about 4555.3337967706. Note that the first 3 decimals coincide. The cubic root of 20751066 is about 274.7979386203.

Adding to 20751066 its reverse (66015702), we get a palindrome (86766768).

The spelling of 20751066 in words is "twenty million, seven hundred fifty-one thousand, sixty-six".