640380105 has 24 divisors (see below), whose sum is σ = 1111723080. Its totient is φ = 341003520.

The previous prime is 640380071. The next prime is 640380119. The reversal of 640380105 is 501083046.

640380105 is a `hidden beast` number, since 640 + 3 + 8 + 0 + 10 + 5 = 666.

640380105 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 54110736 + 586269369 = 7356^2 + 24213^2 .

It is a de Polignac number, because none of the positive numbers 2^k-640380105 is a prime.

It is a super-2 number, since 2×640380105² = 820173357759622050, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 18981 + ... + 40509.

It is an arithmetic number, because the mean of its divisors is an integer number (46321795).

Almost surely, 2^640380105 is an apocalyptic number.

It is an amenable number.

640380105 is a deficient number, since it is larger than the sum of its proper divisors (471342975).

640380105 is a wasteful number, since it uses less digits than its factorization.

640380105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22201 (or 22198 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 640380105 is about 25305.7326509232. The cubic root of 640380105 is about 861.9444487899.

The spelling of 640380105 in words is "six hundred forty million, three hundred eighty thousand, one hundred five".