20404000 has 48 divisors (see below), whose sum is σ = 50142456. Its totient is φ = 8160000.

The previous prime is 20403989. The next prime is 20404009. The reversal of 20404000 is 40402.

It can be written as a sum of positive squares in 4 ways, for example, as 725904 + 19678096 = 852^2 + 4436^2 .

It is a Harshad number since it is a multiple of its sum of digits (10).

It is not an unprimeable number, because it can be changed into a prime (20404009) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1450 + ... + 6550.

Almost surely, 2^20404000 is an apocalyptic number.

20404000 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 20404000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25071228).

20404000 is an abundant number, since it is smaller than the sum of its proper divisors (29738456).

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

20404000 is an equidigital number, since it uses as much as digits as its factorization.

20404000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5126 (or 5108 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 10.

The square root of 20404000 is about 4517.0787019931. The cubic root of 20404000 is about 273.2572992294.

Adding to 20404000 its reverse (40402), we get a palindrome (20444402).

The spelling of 20404000 in words is "twenty million, four hundred four thousand".