1661216006 has 16 divisors (see below), whose sum is σ = 2507839488. Its totient is φ = 825280200.

The previous prime is 1661215991. The next prime is 1661216017. The reversal of 1661216006 is 6006121661.

It is a self number, because there is not a number n which added to its sum of digits gives 1661216006.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 404021 + ... + 408111.

It is an arithmetic number, because the mean of its divisors is an integer number (156739968).

Almost surely, 2^1661216006 is an apocalyptic number.

1661216006 is a deficient number, since it is larger than the sum of its proper divisors (846623482).

1661216006 is a wasteful number, since it uses less digits than its factorization.

1661216006 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5347.

The product of its (nonzero) digits is 2592, while the sum is 29.

The square root of 1661216006 is about 40758.0176897749. The cubic root of 1661216006 is about 1184.3371953792.

Adding to 1661216006 its reverse (6006121661), we get a palindrome (7667337667).

The spelling of 1661216006 in words is "one billion, six hundred sixty-one million, two hundred sixteen thousand, six".