66761161 has 8 divisors (see below), whose sum is σ = 70749000. Its totient is φ = 62885760.

The previous prime is 66761153. The next prime is 66761171. The reversal of 66761161 is 16116766.

It can be written as a sum of positive squares in 4 ways, for example, as 4840000 + 61921161 = 2200^2 + 7869^2 .

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 66761161 - 2³ = 66761153 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66761171) 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, 26886 + ... + 29263.

It is an arithmetic number, because the mean of its divisors is an integer number (8843625).

Almost surely, 2^66761161 is an apocalyptic number.

It is an amenable number.

66761161 is a deficient number, since it is larger than the sum of its proper divisors (3987839).

66761161 is a wasteful number, since it uses less digits than its factorization.

66761161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56219.

The product of its digits is 9072, while the sum is 34.

The square root of 66761161 is about 8170.7503327418. The cubic root of 66761161 is about 405.6716204686.

The spelling of 66761161 in words is "sixty-six million, seven hundred sixty-one thousand, one hundred sixty-one".