640547137 has 2 divisors, whose sum is σ = 640547138. Its totient is φ = 640547136.

The previous prime is 640547119. The next prime is 640547143. The reversal of 640547137 is 731745046.

640547137 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., 560695041 + 79852096 = 23679^2 + 8936^2 .

It is a cyclic number.

It is not a de Polignac number, because 640547137 - 2¹¹ = 640545089 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 640547096 and 640547105.

It is not a weakly prime, because it can be changed into another prime (640547177) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320273568 + 320273569.

It is an arithmetic number, because the mean of its divisors is an integer number (320273569).

Almost surely, 2^640547137 is an apocalyptic number.

It is an amenable number.

640547137 is a deficient number, since it is larger than the sum of its proper divisors (1).

640547137 is an equidigital number, since it uses as much as digits as its factorization.

640547137 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 70560, while the sum is 37.

The square root of 640547137 is about 25309.0327156136. The cubic root of 640547137 is about 862.0193833422.

The spelling of 640547137 in words is "six hundred forty million, five hundred forty-seven thousand, one hundred thirty-seven".