640209617101 has 2 divisors, whose sum is σ = 640209617102. Its totient is φ = 640209617100.

The previous prime is 640209617053. The next prime is 640209617119. The reversal of 640209617101 is 101716902046.

640209617101 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 629404222500 + 10805394601 = 793350^2 + 103949^2 .

It is a cyclic number.

It is not a de Polignac number, because 640209617101 - 2⁷ = 640209616973 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (640209617141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320104808550 + 320104808551.

It is an arithmetic number, because the mean of its divisors is an integer number (320104808551).

Almost surely, 2^640209617101 is an apocalyptic number.

It is an amenable number.

640209617101 is a deficient number, since it is larger than the sum of its proper divisors (1).

640209617101 is an equidigital number, since it uses as much as digits as its factorization.

640209617101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18144, while the sum is 37.

The spelling of 640209617101 in words is "six hundred forty billion, two hundred nine million, six hundred seventeen thousand, one hundred one".