66646875 has 24 divisors (see below), whose sum is σ = 111086640. Its totient is φ = 35540000.

The previous prime is 66646829. The next prime is 66646897. The reversal of 66646875 is 57864666.

It is not a de Polignac number, because 66646875 - 2¹⁰ = 66645851 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5821 + ... + 12929.

It is an arithmetic number, because the mean of its divisors is an integer number (4628610).

Almost surely, 2^66646875 is an apocalyptic number.

66646875 is a deficient number, since it is larger than the sum of its proper divisors (44439765).

66646875 is an frugal number, since it uses more digits than its factorization.

66646875 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7137 (or 7117 counting only the distinct ones).

The product of its digits is 1451520, while the sum is 48.

The square root of 66646875 is about 8163.7537321994. The cubic root of 66646875 is about 405.4400034286.

The spelling of 66646875 in words is "sixty-six million, six hundred forty-six thousand, eight hundred seventy-five".