1663891107 has 4 divisors (see below), whose sum is σ = 2218521480. Its totient is φ = 1109260736.

The previous prime is 1663891067. The next prime is 1663891111. The reversal of 1663891107 is 7011983661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7011983661 = 3 ⋅2337327887.

It is a cyclic number.

It is not a de Polignac number, because 1663891107 - 2⁶ = 1663891043 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1663891157) 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, 277315182 + ... + 277315187.

It is an arithmetic number, because the mean of its divisors is an integer number (554630370).

Almost surely, 2^1663891107 is an apocalyptic number.

1663891107 is a deficient number, since it is larger than the sum of its proper divisors (554630373).

1663891107 is an equidigital number, since it uses as much as digits as its factorization.

1663891107 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 554630372.

The product of its (nonzero) digits is 54432, while the sum is 42.

The square root of 1663891107 is about 40790.8213572612. The cubic root of 1663891107 is about 1184.9725778340.

The spelling of 1663891107 in words is "one billion, six hundred sixty-three million, eight hundred ninety-one thousand, one hundred seven".