66618925 has 12 divisors (see below), whose sum is σ = 86199840. Its totient is φ = 50977520.

The previous prime is 66618917. The next prime is 66618931. The reversal of 66618925 is 52981666.

It is not a de Polignac number, because 66618925 - 2³ = 66618917 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 57355 + ... + 58504.

It is an arithmetic number, because the mean of its divisors is an integer number (7183320).

Almost surely, 2^66618925 is an apocalyptic number.

It is an amenable number.

66618925 is a deficient number, since it is larger than the sum of its proper divisors (19580915).

66618925 is a wasteful number, since it uses less digits than its factorization.

66618925 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115892 (or 115887 counting only the distinct ones).

The product of its digits is 155520, while the sum is 43.

The square root of 66618925 is about 8162.0417176096. The cubic root of 66618925 is about 405.3833184373.

It can be divided in two parts, 666 and 18925, that added together give a palindrome (19591).

The spelling of 66618925 in words is "sixty-six million, six hundred eighteen thousand, nine hundred twenty-five".