1661326206 has 8 divisors (see below), whose sum is σ = 3322652424. Its totient is φ = 553775400.

The previous prime is 1661326157. The next prime is 1661326223. The reversal of 1661326206 is 6026231661.

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

1661326206 is an admirable number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 138443845 + ... + 138443856.

It is an arithmetic number, because the mean of its divisors is an integer number (415331553).

Almost surely, 2^1661326206 is an apocalyptic number.

1661326206 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1661326206 is a wasteful number, since it uses less digits than its factorization.

1661326206 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 276887706.

The product of its (nonzero) digits is 15552, while the sum is 33.

The square root of 1661326206 is about 40759.3695486081. The cubic root of 1661326206 is about 1184.3633832385.

Adding to 1661326206 its reverse (6026231661), we get a palindrome (7687557867).

The spelling of 1661326206 in words is "one billion, six hundred sixty-one million, three hundred twenty-six thousand, two hundred six".