66751887 has 4 divisors (see below), whose sum is σ = 89002520. Its totient is φ = 44501256.

The previous prime is 66751871. The next prime is 66751889. The reversal of 66751887 is 78815766.

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

It is not a de Polignac number, because 66751887 - 2⁴ = 66751871 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 (66751889) 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 3 ways as a sum of consecutive naturals, for example, 11125312 + ... + 11125317.

It is an arithmetic number, because the mean of its divisors is an integer number (22250630).

Almost surely, 2^66751887 is an apocalyptic number.

66751887 is a deficient number, since it is larger than the sum of its proper divisors (22250633).

66751887 is a wasteful number, since it uses less digits than its factorization.

66751887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22250632.

The product of its digits is 564480, while the sum is 48.

The square root of 66751887 is about 8170.1828008925. The cubic root of 66751887 is about 405.6528352309.

The spelling of 66751887 in words is "sixty-six million, seven hundred fifty-one thousand, eight hundred eighty-seven".