661005206 has 8 divisors (see below), whose sum is σ = 1001325024. Its totient is φ = 327230200.

The previous prime is 661005197. The next prime is 661005209. The reversal of 661005206 is 602500166.

661005206 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661005209) 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, 1635950 + ... + 1636353.

It is an arithmetic number, because the mean of its divisors is an integer number (125165628).

Almost surely, 2^661005206 is an apocalyptic number.

661005206 is a deficient number, since it is larger than the sum of its proper divisors (340319818).

661005206 is a wasteful number, since it uses less digits than its factorization.

661005206 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3272406.

The product of its (nonzero) digits is 2160, while the sum is 26.

The square root of 661005206 is about 25710.0215091314. The cubic root of 661005206 is about 871.1005607725.

The spelling of 661005206 in words is "six hundred sixty-one million, five thousand, two hundred six".