20404420400 has 120 divisors (see below), whose sum is σ = 60334409184. Its totient is φ = 6457651200.

The previous prime is 20404420369. The next prime is 20404420403. The reversal of 20404420400 is 402440402.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (20404420403) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 243881 + ... + 316680.

Almost surely, 2^20404420400 is an apocalyptic number.

20404420400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20404420400 is an abundant number, since it is smaller than the sum of its proper divisors (39929988784).

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

20404420400 is a wasteful number, since it uses less digits than its factorization.

20404420400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 560599 (or 560588 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 20.

Adding to 20404420400 its reverse (402440402), we get a palindrome (20806860802).

The spelling of 20404420400 in words is "twenty billion, four hundred four million, four hundred twenty thousand, four hundred".