66956885161 has 8 divisors (see below), whose sum is σ = 69416008200. Its totient is φ = 64507779840.

The previous prime is 66956885147. The next prime is 66956885179. The reversal of 66956885161 is 16158865966.

It can be written as a sum of positive squares in 4 ways, for example, as 936666025 + 66020219136 = 30605^2 + 256944^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66956885161 - 2¹³ = 66956876969 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66956885161.

It is not an unprimeable number, because it can be changed into a prime (66956885101) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2490816 + ... + 2517553.

It is an arithmetic number, because the mean of its divisors is an integer number (8677001025).

Almost surely, 2^66956885161 is an apocalyptic number.

It is an amenable number.

66956885161 is a deficient number, since it is larger than the sum of its proper divisors (2459123039).

66956885161 is a wasteful number, since it uses less digits than its factorization.

66956885161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5008859.

The product of its digits is 18662400, while the sum is 61.

The spelling of 66956885161 in words is "sixty-six billion, nine hundred fifty-six million, eight hundred eighty-five thousand, one hundred sixty-one".