55555777779 has 4 divisors (see below), whose sum is σ = 74074370376. Its totient is φ = 37037185184.

The previous prime is 55555777727. The next prime is 55555777883. The reversal of 55555777779 is 97777755555.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 55555777779 - 2⁸ = 55555777523 is a prime.

It is a plaindrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (55555777279) 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, 9259296294 + ... + 9259296299.

It is an arithmetic number, because the mean of its divisors is an integer number (18518592594).

Almost surely, 2^55555777779 is an apocalyptic number.

55555777779 is a deficient number, since it is larger than the sum of its proper divisors (18518592597).

55555777779 is a wasteful number, since it uses less digits than its factorization.

55555777779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18518592596.

The product of its digits is 472696875, while the sum is 69.

It can be divided in two parts, 555557 and 77779, that added together give a palindrome (633336).

The spelling of 55555777779 in words is "fifty-five billion, five hundred fifty-five million, seven hundred seventy-seven thousand, seven hundred seventy-nine".