78643650001 has 6 divisors (see below), whose sum is σ = 91483429650. Its totient is φ = 67408842816.

The previous prime is 78643649993. The next prime is 78643650011. The reversal of 78643650001 is 10005634687.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 59317089601 + 19326560400 = 243551^2 + 139020^2 .

It is not a de Polignac number, because 78643650001 - 2³ = 78643649993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78643650011) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 802486176 + ... + 802486273.

It is an arithmetic number, because the mean of its divisors is an integer number (15247238275).

Almost surely, 2^78643650001 is an apocalyptic number.

It is an amenable number.

78643650001 is a deficient number, since it is larger than the sum of its proper divisors (12839779649).

78643650001 is a wasteful number, since it uses less digits than its factorization.

78643650001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1604972463 (or 1604972456 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 40.

The spelling of 78643650001 in words is "seventy-eight billion, six hundred forty-three million, six hundred fifty thousand, one".