7912641665 has 8 divisors (see below), whose sum is σ = 9499113000. Its totient is φ = 6327484672.

The previous prime is 7912641661. The next prime is 7912641683. The reversal of 7912641665 is 5661462197.

It can be written as a sum of positive squares in 4 ways, for example, as 5040432016 + 2872209649 = 70996^2 + 53593^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 7912641665 - 2² = 7912641661 is a prime.

It is not an unprimeable number, because it can be changed into a prime (7912641661) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 315290 + ... + 339459.

It is an arithmetic number, because the mean of its divisors is an integer number (1187389125).

Almost surely, 2^7912641665 is an apocalyptic number.

It is an amenable number.

7912641665 is a deficient number, since it is larger than the sum of its proper divisors (1586471335).

7912641665 is a wasteful number, since it uses less digits than its factorization.

7912641665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 657171.

The product of its digits is 544320, while the sum is 47.

The square root of 7912641665 is about 88953.0306678755. The cubic root of 7912641665 is about 1992.6934786278.

The spelling of 7912641665 in words is "seven billion, nine hundred twelve million, six hundred forty-one thousand, six hundred sixty-five".