640101 has 32 divisors (see below), whose sum is σ = 1133568. Its totient is φ = 311040.

The previous prime is 640099. The next prime is 640109. The reversal of 640101 is 101046.

It is not a de Polignac number, because 640101 - 2¹ = 640099 is a prime.

640101 is a modest number, since divided by 101 gives 64 as remainder.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 640101.

It is not an unprimeable number, because it can be changed into a prime (640109) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3846 + ... + 4008.

It is an arithmetic number, because the mean of its divisors is an integer number (35424).

2⁶⁴⁰¹⁰¹ is an apocalyptic number.

It is an amenable number.

640101 is a deficient number, since it is larger than the sum of its proper divisors (493467).

640101 is a wasteful number, since it uses less digits than its factorization.

640101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 201.

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 640101 is about 800.0631225097. The cubic root of 640101 is about 86.1819206525.

Adding to 640101 its reverse (101046), we get a palindrome (741147).

It can be divided in two parts, 640 and 101, that added together give a triangular number (741 = T₃₈).

The spelling of 640101 in words is "six hundred forty thousand, one hundred one".