6661506601 has 4 divisors (see below), whose sum is σ = 6803240832. Its totient is φ = 6519772372.

The previous prime is 6661506589. The next prime is 6661506619. The reversal of 6661506601 is 1066051666.

6661506601 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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 6661506601 - 2¹³ = 6661498409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6661506671) 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, 70867045 + ... + 70867138.

It is an arithmetic number, because the mean of its divisors is an integer number (1700810208).

Almost surely, 2^6661506601 is an apocalyptic number.

It is an amenable number.

6661506601 is a deficient number, since it is larger than the sum of its proper divisors (141734231).

6661506601 is a wasteful number, since it uses less digits than its factorization.

6661506601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 141734230.

The product of its (nonzero) digits is 38880, while the sum is 37.

The square root of 6661506601 is about 81618.0531561492. The cubic root of 6661506601 is about 1881.5863516564.

The spelling of 6661506601 in words is "six billion, six hundred sixty-one million, five hundred six thousand, six hundred one".