1663787927 has 4 divisors (see below), whose sum is σ = 1665599280. Its totient is φ = 1661976576.

The previous prime is 1663787903. The next prime is 1663787963. The reversal of 1663787927 is 7297873661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7297873661 = 13 ⋅561374897.

It is a cyclic number.

It is not a de Polignac number, because 1663787927 - 2¹² = 1663783831 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1663717927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 904298 + ... + 906135.

It is an arithmetic number, because the mean of its divisors is an integer number (416399820).

Almost surely, 2^1663787927 is an apocalyptic number.

1663787927 is a deficient number, since it is larger than the sum of its proper divisors (1811353).

1663787927 is an equidigital number, since it uses as much as digits as its factorization.

1663787927 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1811352.

The product of its digits is 5334336, while the sum is 56.

The square root of 1663787927 is about 40789.5565923436. The cubic root of 1663787927 is about 1184.9480834430.

The spelling of 1663787927 in words is "one billion, six hundred sixty-three million, seven hundred eighty-seven thousand, nine hundred twenty-seven".