66604641 has 16 divisors (see below), whose sum is σ = 90055680. Its totient is φ = 43782480.

The previous prime is 66604631. The next prime is 66604649. The reversal of 66604641 is 14640666.

It is not a de Polignac number, because 66604641 - 2⁵ = 66604609 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (66604649) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 135406 + ... + 135896.

It is an arithmetic number, because the mean of its divisors is an integer number (5628480).

Almost surely, 2^66604641 is an apocalyptic number.

It is an amenable number.

66604641 is a deficient number, since it is larger than the sum of its proper divisors (23451039).

66604641 is a wasteful number, since it uses less digits than its factorization.

66604641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1036.

The product of its (nonzero) digits is 20736, while the sum is 33.

The square root of 66604641 is about 8161.1666445429. The cubic root of 66604641 is about 405.3543431413.

The spelling of 66604641 in words is "sixty-six million, six hundred four thousand, six hundred forty-one".