1663695774 has 40 divisors (see below), whose sum is σ = 4014678360. Its totient is φ = 511905744.

The previous prime is 1663695767. The next prime is 1663695793. The reversal of 1663695774 is 4775963661.

It is a happy number.

1663695774 is a `hidden beast` number, since 1 + 6 + 6 + 3 + 69 + 577 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 1663695774.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 392884 + ... + 397095.

It is an arithmetic number, because the mean of its divisors is an integer number (100366959).

Almost surely, 2^1663695774 is an apocalyptic number.

1663695774 is an abundant number, since it is smaller than the sum of its proper divisors (2350982586).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1663695774 is a wasteful number, since it uses less digits than its factorization.

1663695774 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 790006 (or 789997 counting only the distinct ones).

The product of its digits is 5715360, while the sum is 54.

The square root of 1663695774 is about 40788.4269615782. The cubic root of 1663695774 is about 1184.9262059479.

The spelling of 1663695774 in words is "one billion, six hundred sixty-three million, six hundred ninety-five thousand, seven hundred seventy-four".