66888851 has 4 divisors (see below), whose sum is σ = 66909552. Its totient is φ = 66868152.

The previous prime is 66888841. The next prime is 66888869. The reversal of 66888851 is 15888866.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66888851 - 2¹⁰ = 66887827 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66888851.

It is not an unprimeable number, because it can be changed into a prime (66888821) 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, 4340 + ... + 12353.

It is an arithmetic number, because the mean of its divisors is an integer number (16727388).

Almost surely, 2^66888851 is an apocalyptic number.

66888851 is a deficient number, since it is larger than the sum of its proper divisors (20701).

66888851 is a wasteful number, since it uses less digits than its factorization.

66888851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20700.

The product of its digits is 737280, while the sum is 50.

The square root of 66888851 is about 8178.5604479028. The cubic root of 66888851 is about 405.9300902058.

The spelling of 66888851 in words is "sixty-six million, eight hundred eighty-eight thousand, eight hundred fifty-one".