55121866 has 16 divisors (see below), whose sum is σ = 85876200. Its totient is φ = 26504128.

The previous prime is 55121863. The next prime is 55121881. The reversal of 55121866 is 66812155.

It is a happy number.

55121866 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 43758225 + 11363641 = 6615^2 + 3371^2 .

It is a super-2 number, since 2×55121866² = 6076840222643912, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (55121863) 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 in 7 ways as a sum of consecutive naturals, for example, 13836 + ... + 17368.

Almost surely, 2^55121866 is an apocalyptic number.

55121866 is a deficient number, since it is larger than the sum of its proper divisors (30754334).

55121866 is a wasteful number, since it uses less digits than its factorization.

55121866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3833.

The product of its digits is 14400, while the sum is 34.

The square root of 55121866 is about 7424.4101449206. The cubic root of 55121866 is about 380.5759180332.

The spelling of 55121866 in words is "fifty-five million, one hundred twenty-one thousand, eight hundred sixty-six".