1663427943 has 12 divisors (see below), whose sum is σ = 2411664840. Its totient is φ = 1104827856.

The previous prime is 1663427939. The next prime is 1663427947. The reversal of 1663427943 is 3497243661.

1663427943 is a `hidden beast` number, since 1 + 6 + 634 + 2 + 7 + 9 + 4 + 3 = 666.

It is an interprime number because it is at equal distance from previous prime (1663427939) and next prime (1663427947).

It is not a de Polignac number, because 1663427943 - 2² = 1663427939 is a prime.

It is a super-2 number, since 2×1663427943² = 5533985043106422498, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1663427947) 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 11 ways as a sum of consecutive naturals, for example, 341121 + ... + 345962.

It is an arithmetic number, because the mean of its divisors is an integer number (200972070).

Almost surely, 2^1663427943 is an apocalyptic number.

1663427943 is a deficient number, since it is larger than the sum of its proper divisors (748236897).

1663427943 is a wasteful number, since it uses less digits than its factorization.

1663427943 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 687358 (or 687355 counting only the distinct ones).

The product of its digits is 653184, while the sum is 45.

The square root of 1663427943 is about 40785.1436555028. The cubic root of 1663427943 is about 1184.8626171982.

The spelling of 1663427943 in words is "one billion, six hundred sixty-three million, four hundred twenty-seven thousand, nine hundred forty-three".