66388825 has 24 divisors (see below), whose sum is σ = 89994240. Its totient is φ = 48364800.

The previous prime is 66388783. The next prime is 66388849. The reversal of 66388825 is 52888366.

It is a happy number.

It is not a de Polignac number, because 66388825 - 2⁷ = 66388697 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, 10656 + ... + 15694.

It is an arithmetic number, because the mean of its divisors is an integer number (3749760).

Almost surely, 2^66388825 is an apocalyptic number.

It is an amenable number.

66388825 is a deficient number, since it is larger than the sum of its proper divisors (23605415).

66388825 is a wasteful number, since it uses less digits than its factorization.

66388825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5097 (or 5092 counting only the distinct ones).

The product of its digits is 552960, while the sum is 46.

The square root of 66388825 is about 8147.9337871635. The cubic root of 66388825 is about 404.9160523055.

The spelling of 66388825 in words is "sixty-six million, three hundred eighty-eight thousand, eight hundred twenty-five".