66856394 has 8 divisors (see below), whose sum is σ = 109401408. Its totient is φ = 30389260.

The previous prime is 66856351. The next prime is 66856399. The reversal of 66856394 is 49365866.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (66856399) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1519442 + ... + 1519485.

It is an arithmetic number, because the mean of its divisors is an integer number (13675176).

Almost surely, 2^66856394 is an apocalyptic number.

66856394 is a deficient number, since it is larger than the sum of its proper divisors (42545014).

66856394 is a wasteful number, since it uses less digits than its factorization.

66856394 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3038940.

The product of its digits is 933120, while the sum is 47.

The square root of 66856394 is about 8176.5759337268. The cubic root of 66856394 is about 405.8644220396.

The spelling of 66856394 in words is "sixty-six million, eight hundred fifty-six thousand, three hundred ninety-four".