7688404561 has 4 divisors (see below), whose sum is σ = 7833468852. Its totient is φ = 7543340272.

The previous prime is 7688404543. The next prime is 7688404567. The reversal of 7688404561 is 1654048867.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5208364561 + 2480040000 = 72169^2 + 49800^2 .

It is a cyclic number.

It is not a de Polignac number, because 7688404561 - 2¹⁹ = 7687880273 is a prime.

It is a super-2 number, since 2×7688404561² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7688404567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 72532066 + ... + 72532171.

It is an arithmetic number, because the mean of its divisors is an integer number (1958367213).

Almost surely, 2^7688404561 is an apocalyptic number.

It is an amenable number.

7688404561 is a deficient number, since it is larger than the sum of its proper divisors (145064291).

7688404561 is a wasteful number, since it uses less digits than its factorization.

7688404561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145064290.

The product of its (nonzero) digits is 1290240, while the sum is 49.

The square root of 7688404561 is about 87683.5478353836. The cubic root of 7688404561 is about 1973.6890995141.

The spelling of 7688404561 in words is "seven billion, six hundred eighty-eight million, four hundred four thousand, five hundred sixty-one".