78780662869 has 4 divisors (see below), whose sum is σ = 79309392300. Its totient is φ = 78251933440.

The previous prime is 78780662819. The next prime is 78780662893. The reversal of 78780662869 is 96826608787.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 96826608787 = 383 ⋅252810989.

It can be written as a sum of positive squares in 2 ways, for example, as 18512867844 + 60267795025 = 136062^2 + 245495^2 .

It is a cyclic number.

It is not a de Polignac number, because 78780662869 - 2³⁵ = 44420924501 is a prime.

It is a super-2 number, since 2×78780662869² (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 (78780662809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 264364492 + ... + 264364789.

It is an arithmetic number, because the mean of its divisors is an integer number (19827348075).

Almost surely, 2^78780662869 is an apocalyptic number.

It is an amenable number.

78780662869 is a deficient number, since it is larger than the sum of its proper divisors (528729431).

78780662869 is a wasteful number, since it uses less digits than its factorization.

78780662869 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 528729430.

The product of its (nonzero) digits is 97542144, while the sum is 67.

The spelling of 78780662869 in words is "seventy-eight billion, seven hundred eighty million, six hundred sixty-two thousand, eight hundred sixty-nine".