6400404002 has 4 divisors (see below), whose sum is σ = 9600606006. Its totient is φ = 3200202000.

The previous prime is 6400403981. The next prime is 6400404053. The reversal of 6400404002 is 2004040046.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 6399840001 + 564001 = 79999^2 + 751^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1600100999 + ... + 1600101002.

Almost surely, 2^6400404002 is an apocalyptic number.

6400404002 is a deficient number, since it is larger than the sum of its proper divisors (3200202004).

6400404002 is a wasteful number, since it uses less digits than its factorization.

6400404002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3200202003.

The product of its (nonzero) digits is 768, while the sum is 20.

The square root of 6400404002 is about 80002.5249726532. The cubic root of 6400404002 is about 1856.6745995225.

Adding to 6400404002 its reverse (2004040046), we get a palindrome (8404444048).

The spelling of 6400404002 in words is "six billion, four hundred million, four hundred four thousand, two".