66705855 has 32 divisors (see below), whose sum is σ = 109105920. Its totient is φ = 34794240.

The previous prime is 66705823. The next prime is 66705869. The reversal of 66705855 is 55850766.

It is not a de Polignac number, because 66705855 - 2⁵ = 66705823 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 162891 + ... + 163299.

It is an arithmetic number, because the mean of its divisors is an integer number (3409560).

Almost surely, 2^66705855 is an apocalyptic number.

66705855 is a deficient number, since it is larger than the sum of its proper divisors (42400065).

66705855 is a wasteful number, since it uses less digits than its factorization.

66705855 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 631.

The product of its (nonzero) digits is 252000, while the sum is 42.

The square root of 66705855 is about 8167.3652422308. The cubic root of 66705855 is about 405.5595679287.

The spelling of 66705855 in words is "sixty-six million, seven hundred five thousand, eight hundred fifty-five".