20443780 has 72 divisors (see below), whose sum is σ = 52170048. Its totient is φ = 6697152.

The previous prime is 20443771. The next prime is 20443781. The reversal of 20443780 is 8734402.

It is a super-3 number, since 3×20443780³ (a number of 23 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is not an unprimeable number, because it can be changed into a prime (20443781) 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 23 ways as a sum of consecutive naturals, for example, 22087 + ... + 22993.

It is an arithmetic number, because the mean of its divisors is an integer number (724584).

Almost surely, 2^20443780 is an apocalyptic number.

20443780 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 20443780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26085024).

20443780 is an abundant number, since it is smaller than the sum of its proper divisors (31726268).

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

20443780 is a wasteful number, since it uses less digits than its factorization.

20443780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 953 (or 944 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 28.

The square root of 20443780 is about 4521.4798462450. The cubic root of 20443780 is about 273.4347663727.

The spelling of 20443780 in words is "twenty million, four hundred forty-three thousand, seven hundred eighty".