66888223 has 2 divisors, whose sum is σ = 66888224. Its totient is φ = 66888222.

The previous prime is 66888197. The next prime is 66888229. The reversal of 66888223 is 32288866.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66888223 - 2¹³ = 66880031 is a prime.

It is equal to p_3945589 and since 66888223 and 3945589 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66888223.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66888229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33444111 + 33444112.

It is an arithmetic number, because the mean of its divisors is an integer number (33444112).

Almost surely, 2^66888223 is an apocalyptic number.

66888223 is a deficient number, since it is larger than the sum of its proper divisors (1).

66888223 is an equidigital number, since it uses as much as digits as its factorization.

66888223 is an evil number, because the sum of its binary digits is even.

The product of its digits is 221184, while the sum is 43.

The square root of 66888223 is about 8178.5220547480. The cubic root of 66888223 is about 405.9288198153.

The spelling of 66888223 in words is "sixty-six million, eight hundred eighty-eight thousand, two hundred twenty-three".