978009720017 has 4 divisors (see below), whose sum is σ = 1066919694576. Its totient is φ = 889099745460.

The previous prime is 978009720011. The next prime is 978009720049. The reversal of 978009720017 is 710027900879.

978009720017 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 978009720017 - 2⁸ = 978009719761 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (978009720011) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 44454987263 + ... + 44454987284.

It is an arithmetic number, because the mean of its divisors is an integer number (266729923644).

Almost surely, 2^978009720017 is an apocalyptic number.

It is an amenable number.

978009720017 is a deficient number, since it is larger than the sum of its proper divisors (88909974559).

978009720017 is a wasteful number, since it uses less digits than its factorization.

978009720017 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88909974558.

The product of its (nonzero) digits is 444528, while the sum is 50.

The spelling of 978009720017 in words is "nine hundred seventy-eight billion, nine million, seven hundred twenty thousand, seventeen".