78531557773 has 4 divisors (see below), whose sum is σ = 78877512000. Its totient is φ = 78185603548.

The previous prime is 78531557707. The next prime is 78531557849. The reversal of 78531557773 is 37775513587.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 78531557773 - 2³³ = 69941623181 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78531557173) 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, 172976773 + ... + 172977226.

It is an arithmetic number, because the mean of its divisors is an integer number (19719378000).

Almost surely, 2^78531557773 is an apocalyptic number.

It is an amenable number.

78531557773 is a deficient number, since it is larger than the sum of its proper divisors (345954227).

78531557773 is a wasteful number, since it uses less digits than its factorization.

78531557773 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 345954226.

The product of its digits is 21609000, while the sum is 58.

The spelling of 78531557773 in words is "seventy-eight billion, five hundred thirty-one million, five hundred fifty-seven thousand, seven hundred seventy-three".