640474401002 has 8 divisors (see below), whose sum is σ = 986676780036. Its totient is φ = 311582140992.

The previous prime is 640474400999. The next prime is 640474401023. The reversal of 640474401002 is 200104474046.

It can be written as a sum of positive squares in 2 ways, for example, as 633789539881 + 6684861121 = 796109^2 + 81761^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 640474401002.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4327529663 + ... + 4327529810.

Almost surely, 2^640474401002 is an apocalyptic number.

640474401002 is a deficient number, since it is larger than the sum of its proper divisors (346202379034).

640474401002 is a wasteful number, since it uses less digits than its factorization.

640474401002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8655059512.

The product of its (nonzero) digits is 21504, while the sum is 32.

Adding to 640474401002 its reverse (200104474046), we get a palindrome (840578875048).

The spelling of 640474401002 in words is "six hundred forty billion, four hundred seventy-four million, four hundred one thousand, two".