66551212215 has 12 divisors (see below), whose sum is σ = 115355434584. Its totient is φ = 35493979824.

The previous prime is 66551212159. The next prime is 66551212229. The reversal of 66551212215 is 51221215566.

66551212215 is a `hidden beast` number, since 6 + 6 + 5 + 512 + 122 + 15 = 666.

It is not a de Polignac number, because 66551212215 - 2⁶ = 66551212151 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66551212215.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 739457869 + ... + 739457958.

It is an arithmetic number, because the mean of its divisors is an integer number (9612952882).

Almost surely, 2^66551212215 is an apocalyptic number.

66551212215 is a deficient number, since it is larger than the sum of its proper divisors (48804222369).

66551212215 is a wasteful number, since it uses less digits than its factorization.

66551212215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1478915838 (or 1478915835 counting only the distinct ones).

The product of its digits is 36000, while the sum is 36.

The spelling of 66551212215 in words is "sixty-six billion, five hundred fifty-one million, two hundred twelve thousand, two hundred fifteen".