7646886721 has 4 divisors (see below), whose sum is σ = 7910572500. Its totient is φ = 7383200944.

The previous prime is 7646886713. The next prime is 7646886749. The reversal of 7646886721 is 1276886467.

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 3436304400 + 4210582321 = 58620^2 + 64889^2 .

It is not a de Polignac number, because 7646886721 - 2³ = 7646886713 is a prime.

It is a super-2 number, since 2×7646886721² (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 (7646886701) 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, 131842846 + ... + 131842903.

It is an arithmetic number, because the mean of its divisors is an integer number (1977643125).

Almost surely, 2^7646886721 is an apocalyptic number.

It is an amenable number.

7646886721 is a deficient number, since it is larger than the sum of its proper divisors (263685779).

7646886721 is a wasteful number, since it uses less digits than its factorization.

7646886721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 263685778.

The product of its digits is 5419008, while the sum is 55.

The square root of 7646886721 is about 87446.4791801248. The cubic root of 7646886721 is about 1970.1300060218.

The spelling of 7646886721 in words is "seven billion, six hundred forty-six million, eight hundred eighty-six thousand, seven hundred twenty-one".