2206551666 has 32 divisors (see below), whose sum is σ = 4969598976. Its totient is φ = 647082000.

The previous prime is 2206551631. The next prime is 2206551671. The reversal of 2206551666 is 6661556022.

It is a happy number.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 537190 + ... + 541281.

It is an arithmetic number, because the mean of its divisors is an integer number (155299968).

Almost surely, 2^2206551666 is an apocalyptic number.

2206551666 is an abundant number, since it is smaller than the sum of its proper divisors (2763047310).

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

2206551666 is a wasteful number, since it uses less digits than its factorization.

2206551666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1078518.

The product of its (nonzero) digits is 129600, while the sum is 39.

The square root of 2206551666 is about 46973.9466725971. The cubic root of 2206551666 is about 1301.8812341378.

The spelling of 2206551666 in words is "two billion, two hundred six million, five hundred fifty-one thousand, six hundred sixty-six".