506556691 has 2 divisors, whose sum is σ = 506556692. Its totient is φ = 506556690.

The previous prime is 506556637. The next prime is 506556707. The reversal of 506556691 is 196655605.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 506556691 - 2¹⁹ = 506032403 is a prime.

It is not a weakly prime, because it can be changed into another prime (506556091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 253278345 + 253278346.

It is an arithmetic number, because the mean of its divisors is an integer number (253278346).

Almost surely, 2^506556691 is an apocalyptic number.

506556691 is a deficient number, since it is larger than the sum of its proper divisors (1).

506556691 is an equidigital number, since it uses as much as digits as its factorization.

506556691 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 243000, while the sum is 43.

The square root of 506556691 is about 22506.8143236665. The cubic root of 506556691 is about 797.1548365308.

The spelling of 506556691 in words is "five hundred six million, five hundred fifty-six thousand, six hundred ninety-one".