66641072657 has 4 divisors (see below), whose sum is σ = 67082404416. Its totient is φ = 66199740900.

The previous prime is 66641072623. The next prime is 66641072669. The reversal of 66641072657 is 75627014666.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 66641072657 - 2¹⁰ = 66641071633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66641072677) 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, 220665653 + ... + 220665954.

It is an arithmetic number, because the mean of its divisors is an integer number (16770601104).

Almost surely, 2^66641072657 is an apocalyptic number.

It is an amenable number.

66641072657 is a deficient number, since it is larger than the sum of its proper divisors (441331759).

66641072657 is a wasteful number, since it uses less digits than its factorization.

66641072657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 441331758.

The product of its (nonzero) digits is 2540160, while the sum is 50.

The spelling of 66641072657 in words is "sixty-six billion, six hundred forty-one million, seventy-two thousand, six hundred fifty-seven".