55218169 has 2 divisors, whose sum is σ = 55218170. Its totient is φ = 55218168.

The previous prime is 55218113. The next prime is 55218187. The reversal of 55218169 is 96181255.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 41990400 + 13227769 = 6480^2 + 3637^2 .

It is a cyclic number.

It is not a de Polignac number, because 55218169 - 2¹¹ = 55216121 is a prime.

It is a super-2 number, since 2×55218169² = 6098092375425122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (55218109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27609084 + 27609085.

It is an arithmetic number, because the mean of its divisors is an integer number (27609085).

Almost surely, 2^55218169 is an apocalyptic number.

It is an amenable number.

55218169 is a deficient number, since it is larger than the sum of its proper divisors (1).

55218169 is an equidigital number, since it uses as much as digits as its factorization.

55218169 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21600, while the sum is 37.

The square root of 55218169 is about 7430.8928804014. The cubic root of 55218169 is about 380.7974228672.

It can be divided in two parts, 552 and 18169, that added together give a triangular number (18721 = T₁₉₃).

The spelling of 55218169 in words is "fifty-five million, two hundred eighteen thousand, one hundred sixty-nine".