78625533209 has 4 divisors (see below), whose sum is σ = 78678624180. Its totient is φ = 78572442240.

The previous prime is 78625533193. The next prime is 78625533241. The reversal of 78625533209 is 90233552687.

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 55337857600 + 23287675609 = 235240^2 + 152603^2 .

It is a cyclic number.

It is not a de Polignac number, because 78625533209 - 2⁴ = 78625533193 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (78625533509) 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, 26543264 + ... + 26546225.

It is an arithmetic number, because the mean of its divisors is an integer number (19669656045).

Almost surely, 2^78625533209 is an apocalyptic number.

It is an amenable number.

78625533209 is a deficient number, since it is larger than the sum of its proper divisors (53090971).

78625533209 is a wasteful number, since it uses less digits than its factorization.

78625533209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53090970.

The product of its (nonzero) digits is 2721600, while the sum is 50.

The spelling of 78625533209 in words is "seventy-eight billion, six hundred twenty-five million, five hundred thirty-three thousand, two hundred nine".