556609991 has 8 divisors (see below), whose sum is σ = 656646144. Its totient is φ = 461703960.

The previous prime is 556609957. The next prime is 556610003. The reversal of 556609991 is 199906655.

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

It is a cyclic number.

It is not a de Polignac number, because 556609991 - 2¹⁰ = 556608967 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (556603991) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1282295 + ... + 1282728.

It is an arithmetic number, because the mean of its divisors is an integer number (82080768).

Almost surely, 2^556609991 is an apocalyptic number.

556609991 is a deficient number, since it is larger than the sum of its proper divisors (100036153).

556609991 is a wasteful number, since it uses less digits than its factorization.

556609991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2565061.

The product of its (nonzero) digits is 656100, while the sum is 50.

The square root of 556609991 is about 23592.5833897011. The cubic root of 556609991 is about 822.5904550327.

The spelling of 556609991 in words is "five hundred fifty-six million, six hundred nine thousand, nine hundred ninety-one".