20444400 has 150 divisors (see below), whose sum is σ = 73489592. Its totient is φ = 5443200.

The previous prime is 20444381. The next prime is 20444429. The reversal of 20444400 is 444402.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (150).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 32085 + ... + 32715.

Almost surely, 2^20444400 is an apocalyptic number.

20444400 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 20444400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36744796).

20444400 is an abundant number, since it is smaller than the sum of its proper divisors (53045192).

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

20444400 is a wasteful number, since it uses less digits than its factorization.

20444400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 661 (or 641 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 18.

The square root of 20444400 is about 4521.5484073490. The cubic root of 20444400 is about 273.4375305034.

Adding to 20444400 its reverse (444402), we get a palindrome (20888802).

The spelling of 20444400 in words is "twenty million, four hundred forty-four thousand, four hundred".