556213666 has 8 divisors (see below), whose sum is σ = 842581404. Its totient is φ = 275353200.

The previous prime is 556213663. The next prime is 556213673. The reversal of 556213666 is 666312655.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 505305441 + 50908225 = 22479^2 + 7135^2 .

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

It is not an unprimeable number, because it can be changed into a prime (556213663) 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, 1376565 + ... + 1376968.

Almost surely, 2^556213666 is an apocalyptic number.

556213666 is a deficient number, since it is larger than the sum of its proper divisors (286367738).

556213666 is a wasteful number, since it uses less digits than its factorization.

556213666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2753636.

The product of its digits is 194400, while the sum is 40.

The square root of 556213666 is about 23584.1825383031. The cubic root of 556213666 is about 822.3951713359.

The spelling of 556213666 in words is "five hundred fifty-six million, two hundred thirteen thousand, six hundred sixty-six".