640777090267 has 2 divisors, whose sum is σ = 640777090268. Its totient is φ = 640777090266.

The previous prime is 640777090253. The next prime is 640777090307. The reversal of 640777090267 is 762090777046.

640777090267 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-640777090267 is a prime.

It is a super-2 number, since 2×640777090267² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (640777090237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320388545133 + 320388545134.

It is an arithmetic number, because the mean of its divisors is an integer number (320388545134).

Almost surely, 2^640777090267 is an apocalyptic number.

640777090267 is a deficient number, since it is larger than the sum of its proper divisors (1).

640777090267 is an equidigital number, since it uses as much as digits as its factorization.

640777090267 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6223392, while the sum is 55.

The spelling of 640777090267 in words is "six hundred forty billion, seven hundred seventy-seven million, ninety thousand, two hundred sixty-seven".