54991778 has 4 divisors (see below), whose sum is σ = 82487670. Its totient is φ = 27495888.

The previous prime is 54991777. The next prime is 54991813. The reversal of 54991778 is 87719945.

54991778 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in only one way, i.e., 39601849 + 15389929 = 6293^2 + 3923^2 .

It is not an unprimeable number, because it can be changed into a prime (54991771) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13747943 + ... + 13747946.

Almost surely, 2^54991778 is an apocalyptic number.

54991778 is a deficient number, since it is larger than the sum of its proper divisors (27495892).

54991778 is a wasteful number, since it uses less digits than its factorization.

54991778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27495891.

The product of its digits is 635040, while the sum is 50.

The square root of 54991778 is about 7415.6441392505. The cubic root of 54991778 is about 380.2762949044.

The spelling of 54991778 in words is "fifty-four million, nine hundred ninety-one thousand, seven hundred seventy-eight".