2705686140609 has 27 divisors (see below), whose sum is σ = 3922255526787. Its totient is φ = 1797332894784.

The previous prime is 2705686140569. The next prime is 2705686140649. The reversal of 2705686140609 is 9060416865072.

The square root of 2705686140609 is 1644897.

It is a perfect power (a square), and thus also a powerful number.

2705686140609 is a `hidden beast` number, since 2 + 7 + 0 + 568 + 6 + 14 + 0 + 60 + 9 = 666.

It is an interprime number because it is at equal distance from previous prime (2705686140569) and next prime (2705686140649).

It can be written as a sum of positive squares in only one way, i.e., 729614930625 + 1976071209984 = 854175^2 + 1405728^2 .

It is not a de Polignac number, because 2705686140609 - 2¹³ = 2705686132417 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2705686140649) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1662990054 + ... + 1662991680.

Almost surely, 2^{2705686140609} is an apocalyptic number.

2705686140609 is the 1644897-th square number.

2705686140609 is the 822449-th centered octagonal number.

It is an amenable number.

2705686140609 is a deficient number, since it is larger than the sum of its proper divisors (1216569386178).

2705686140609 is an frugal number, since it uses more digits than its factorization.

2705686140609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3934 (or 1967 counting only the distinct ones).

The product of its (nonzero) digits is 4354560, while the sum is 54.

The spelling of 2705686140609 in words is "two trillion, seven hundred five billion, six hundred eighty-six million, one hundred forty thousand, six hundred nine".