66855855 has 64 divisors (see below), whose sum is σ = 122923008. Its totient is φ = 30735360.

The previous prime is 66855827. The next prime is 66855881. The reversal of 66855855 is 55855866.

It is not a de Polignac number, because 66855855 - 2⁵ = 66855823 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 286819 + ... + 287051.

It is an arithmetic number, because the mean of its divisors is an integer number (1920672).

Almost surely, 2^66855855 is an apocalyptic number.

66855855 is a deficient number, since it is larger than the sum of its proper divisors (56067153).

66855855 is a wasteful number, since it uses less digits than its factorization.

66855855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 336.

The product of its digits is 1440000, while the sum is 48.

The square root of 66855855 is about 8176.5429736534. The cubic root of 66855855 is about 405.8633313361.

The spelling of 66855855 in words is "sixty-six million, eight hundred fifty-five thousand, eight hundred fifty-five".