66854821 has 8 divisors (see below), whose sum is σ = 74484864. Its totient is φ = 59483520.

The previous prime is 66854791. The next prime is 66854861. The reversal of 66854821 is 12845866.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66854821 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66854861) by changing a digit.

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, 64140 + ... + 65173.

It is an arithmetic number, because the mean of its divisors is an integer number (9310608).

Almost surely, 2^66854821 is an apocalyptic number.

It is an amenable number.

66854821 is a deficient number, since it is larger than the sum of its proper divisors (7630043).

66854821 is a wasteful number, since it uses less digits than its factorization.

66854821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129371.

The product of its digits is 92160, while the sum is 40.

The square root of 66854821 is about 8176.4797437528. The cubic root of 66854821 is about 405.8612389497.

The spelling of 66854821 in words is "sixty-six million, eight hundred fifty-four thousand, eight hundred twenty-one".