66220856 has 16 divisors (see below), whose sum is σ = 133715400. Its totient is φ = 30563424.

The previous prime is 66220849. The next prime is 66220877. The reversal of 66220856 is 65802266.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 318266 + ... + 318473.

Almost surely, 2^66220856 is an apocalyptic number.

It is an amenable number.

66220856 is an abundant number, since it is smaller than the sum of its proper divisors (67494544).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66220856 is a wasteful number, since it uses less digits than its factorization.

66220856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 636758 (or 636754 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 35.

The square root of 66220856 is about 8137.6197994254. The cubic root of 66220856 is about 404.5742739772.

It can be divided in two parts, 66220 and 856, that added together give a palindrome (67076).

The spelling of 66220856 in words is "sixty-six million, two hundred twenty thousand, eight hundred fifty-six".