640143221401 has 4 divisors (see below), whose sum is σ = 644070480592. Its totient is φ = 636215962212.

The previous prime is 640143221383. The next prime is 640143221407. The reversal of 640143221401 is 104122341046.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 640143221401 - 2¹³ = 640143213209 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 640143221401.

It is not an unprimeable number, because it can be changed into a prime (640143221407) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1963629351 + ... + 1963629676.

It is an arithmetic number, because the mean of its divisors is an integer number (161017620148).

Almost surely, 2^640143221401 is an apocalyptic number.

It is an amenable number.

640143221401 is a deficient number, since it is larger than the sum of its proper divisors (3927259191).

640143221401 is a wasteful number, since it uses less digits than its factorization.

640143221401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3927259190.

The product of its (nonzero) digits is 4608, while the sum is 28.

Adding to 640143221401 its reverse (104122341046), we get a palindrome (744265562447).

The spelling of 640143221401 in words is "six hundred forty billion, one hundred forty-three million, two hundred twenty-one thousand, four hundred one".