55544399778 has 256 divisors, whose sum is σ = 148925952000. Its totient is φ = 13426974720.

The previous prime is 55544399749. The next prime is 55544399809. The reversal of 55544399778 is 87799344555.

It is a happy number.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 20578273 + ... + 20580971.

It is an arithmetic number, because the mean of its divisors is an integer number (581742000).

Almost surely, 2^55544399778 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 55544399778, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (74462976000).

55544399778 is an abundant number, since it is smaller than the sum of its proper divisors (93381552222).

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

55544399778 is a wasteful number, since it uses less digits than its factorization.

55544399778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2825.

The product of its digits is 190512000, while the sum is 66.

The spelling of 55544399778 in words is "fifty-five billion, five hundred forty-four million, three hundred ninety-nine thousand, seven hundred seventy-eight".