66560651 has 4 divisors (see below), whose sum is σ = 66656304. Its totient is φ = 66465000.

The previous prime is 66560647. The next prime is 66560653. The reversal of 66560651 is 15606566.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15606566 = 2 ⋅7803283.

It is a cyclic number.

It is not a de Polignac number, because 66560651 - 2² = 66560647 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66560653) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46775 + ... + 48176.

It is an arithmetic number, because the mean of its divisors is an integer number (16664076).

Almost surely, 2^66560651 is an apocalyptic number.

66560651 is a deficient number, since it is larger than the sum of its proper divisors (95653).

66560651 is an equidigital number, since it uses as much as digits as its factorization.

66560651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95652.

The product of its (nonzero) digits is 32400, while the sum is 35.

The square root of 66560651 is about 8158.4711190271. The cubic root of 66560651 is about 405.2650827713.

It can be divided in two parts, 665 and 60651, that added together give a palindrome (61316).

The spelling of 66560651 in words is "sixty-six million, five hundred sixty thousand, six hundred fifty-one".