1663293643 has 4 divisors (see below), whose sum is σ = 1814502168. Its totient is φ = 1512085120.

The previous prime is 1663293631. The next prime is 1663293661. The reversal of 1663293643 is 3463923661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3463923661 = 11 ⋅314902151.

It is a cyclic number.

It is not a de Polignac number, because 1663293643 - 2²⁵ = 1629739211 is a prime.

It is a super-2 number, since 2×1663293643² = 5533091485688422898, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1663293643.

It is not an unprimeable number, because it can be changed into a prime (1663293613) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 75604246 + ... + 75604267.

It is an arithmetic number, because the mean of its divisors is an integer number (453625542).

Almost surely, 2^1663293643 is an apocalyptic number.

1663293643 is a deficient number, since it is larger than the sum of its proper divisors (151208525).

1663293643 is a wasteful number, since it uses less digits than its factorization.

1663293643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151208524.

The product of its digits is 419904, while the sum is 43.

The square root of 1663293643 is about 40783.4971894270. The cubic root of 1663293643 is about 1184.8307289655.

The spelling of 1663293643 in words is "one billion, six hundred sixty-three million, two hundred ninety-three thousand, six hundred forty-three".