78505791650 has 48 divisors (see below), whose sum is σ = 171548895168. Its totient is φ = 26351592000.

The previous prime is 78505791643. The next prime is 78505791653. The reversal of 78505791650 is 5619750587.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 78505791592 and 78505791601.

It is not an unprimeable number, because it can be changed into a prime (78505791653) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5482766 + ... + 5497065.

It is an arithmetic number, because the mean of its divisors is an integer number (3573935316).

Almost surely, 2^78505791650 is an apocalyptic number.

78505791650 is an abundant number, since it is smaller than the sum of its proper divisors (93043103518).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

78505791650 is a wasteful number, since it uses less digits than its factorization.

78505791650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10979867 (or 10979862 counting only the distinct ones).

The product of its (nonzero) digits is 2646000, while the sum is 53.

The spelling of 78505791650 in words is "seventy-eight billion, five hundred five million, seven hundred ninety-one thousand, six hundred fifty".