78633335861 has 4 divisors (see below), whose sum is σ = 79134185292. Its totient is φ = 78132486432.

The previous prime is 78633335857. The next prime is 78633335863. The reversal of 78633335861 is 16853333687.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16853333687 = 71 ⋅237370897.

It can be written as a sum of positive squares in 2 ways, for example, as 53107202500 + 25526133361 = 230450^2 + 159769^2 .

It is a cyclic number.

It is not a de Polignac number, because 78633335861 - 2² = 78633335857 is a prime.

It is a super-2 number, since 2×78633335861² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78633335863) 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, 250424480 + ... + 250424793.

It is an arithmetic number, because the mean of its divisors is an integer number (19783546323).

Almost surely, 2^78633335861 is an apocalyptic number.

It is an amenable number.

78633335861 is a deficient number, since it is larger than the sum of its proper divisors (500849431).

78633335861 is a wasteful number, since it uses less digits than its factorization.

78633335861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 500849430.

The product of its digits is 6531840, while the sum is 53.

The spelling of 78633335861 in words is "seventy-eight billion, six hundred thirty-three million, three hundred thirty-five thousand, eight hundred sixty-one".