20444430400 has 84 divisors (see below), whose sum is σ = 50494150980. Its totient is φ = 8147200000.

The previous prime is 20444430379. The next prime is 20444430431. The reversal of 20444430400 is 403444402.

It can be written as a sum of positive squares in 6 ways, for example, as 2518433856 + 17925996544 = 50184^2 + 133888^2 .

It is a Harshad number since it is a multiple of its sum of digits (25).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 406650 + ... + 454150.

It is an arithmetic number, because the mean of its divisors is an integer number (601120845).

Almost surely, 2^20444430400 is an apocalyptic number.

20444430400 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 20444430400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25247075490).

20444430400 is an abundant number, since it is smaller than the sum of its proper divisors (30049720580).

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

20444430400 is a wasteful number, since it uses less digits than its factorization.

20444430400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47792 (or 47777 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 25.

Subtracting from 20444430400 its product of nonzero digits (6144), we obtain a square (20444424256 = 142984²).

Adding to 20444430400 its reverse (403444402), we get a palindrome (20847874802).

The spelling of 20444430400 in words is "twenty billion, four hundred forty-four million, four hundred thirty thousand, four hundred".