20404040004 has 18 divisors (see below), whose sum is σ = 51576878990. Its totient is φ = 6801346656.

The previous prime is 20404040003. The next prime is 20404040021. The reversal of 20404040004 is 40004040402.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 19847174400 + 556865604 = 140880^2 + 23598^2 .

It is a tau number, because it is divible by the number of its divisors (18).

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

It is not an unprimeable number, because it can be changed into a prime (20404040003) 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 5 ways as a sum of consecutive naturals, for example, 283389409 + ... + 283389480.

Almost surely, 2^20404040004 is an apocalyptic number.

It is an amenable number.

20404040004 is an abundant number, since it is smaller than the sum of its proper divisors (31172838986).

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

20404040004 is a wasteful number, since it uses less digits than its factorization.

20404040004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 566778899 (or 566778894 counting only the distinct ones).

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

Adding to 20404040004 its reverse (40004040402), we get a palindrome (60408080406).

The spelling of 20404040004 in words is "twenty billion, four hundred four million, forty thousand, four".