6661172061 has 6 divisors (see below), whose sum is σ = 9621692990. Its totient is φ = 4440781368.

The previous prime is 6661172053. The next prime is 6661172131. The reversal of 6661172061 is 1602711666.

It can be written as a sum of positive squares in only one way, i.e., 6336956025 + 324216036 = 79605^2 + 18006^2 .

It is not a de Polignac number, because 6661172061 - 2³ = 6661172053 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6661172261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 370065106 + ... + 370065123.

Almost surely, 2^6661172061 is an apocalyptic number.

It is an amenable number.

6661172061 is a deficient number, since it is larger than the sum of its proper divisors (2960520929).

6661172061 is a wasteful number, since it uses less digits than its factorization.

6661172061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 740130235 (or 740130232 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 6661172061 is about 81616.0037063810. The cubic root of 6661172061 is about 1881.5548534547.

The spelling of 6661172061 in words is "six billion, six hundred sixty-one million, one hundred seventy-two thousand, sixty-one".