66561206 has 16 divisors (see below), whose sum is σ = 104358240. Its totient is φ = 31799040.

The previous prime is 66561197. The next prime is 66561211. The reversal of 66561206 is 60216566.

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 7 ways as a sum of consecutive naturals, for example, 290 + ... + 11541.

It is an arithmetic number, because the mean of its divisors is an integer number (6522390).

Almost surely, 2^66561206 is an apocalyptic number.

66561206 is a deficient number, since it is larger than the sum of its proper divisors (37797034).

66561206 is a wasteful number, since it uses less digits than its factorization.

66561206 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11959.

The product of its (nonzero) digits is 12960, while the sum is 32.

The square root of 66561206 is about 8158.5051326821. The cubic root of 66561206 is about 405.2662091700.

The spelling of 66561206 in words is "sixty-six million, five hundred sixty-one thousand, two hundred six".