640201640101 has 4 divisors (see below), whose sum is σ = 640440791692. Its totient is φ = 639962488512.

The previous prime is 640201640069. The next prime is 640201640123. The reversal of 640201640101 is 101046102046.

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

It can be written as a sum of positive squares in 2 ways, for example, as 47495664225 + 592705975876 = 217935^2 + 769874^2 .

It is a cyclic number.

It is not a de Polignac number, because 640201640101 - 2⁵ = 640201640069 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640201647101) 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, 119571780 + ... + 119577133.

It is an arithmetic number, because the mean of its divisors is an integer number (160110197923).

Almost surely, 2^640201640101 is an apocalyptic number.

It is an amenable number.

640201640101 is a deficient number, since it is larger than the sum of its proper divisors (239151591).

640201640101 is a wasteful number, since it uses less digits than its factorization.

640201640101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 239151590.

The product of its (nonzero) digits is 1152, while the sum is 25.

Adding to 640201640101 its reverse (101046102046), we get a palindrome (741247742147).

The spelling of 640201640101 in words is "six hundred forty billion, two hundred one million, six hundred forty thousand, one hundred one".