1663787967 has 4 divisors (see below), whose sum is σ = 2218383960. Its totient is φ = 1109191976.

The previous prime is 1663787963. The next prime is 1663787981. The reversal of 1663787967 is 7697873661.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1663787967 - 2² = 1663787963 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1663787967.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1663787963) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 277297992 + ... + 277297997.

It is an arithmetic number, because the mean of its divisors is an integer number (554595990).

Almost surely, 2^1663787967 is an apocalyptic number.

1663787967 is a deficient number, since it is larger than the sum of its proper divisors (554595993).

1663787967 is an equidigital number, since it uses as much as digits as its factorization.

1663787967 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 554595992.

The product of its digits is 16003008, while the sum is 60.

The square root of 1663787967 is about 40789.5570826652. The cubic root of 1663787967 is about 1184.9480929390.

It can be divided in two parts, 166378 and 7967, that added together give a triangular number (174345 = T₅₉₀).

The spelling of 1663787967 in words is "one billion, six hundred sixty-three million, seven hundred eighty-seven thousand, nine hundred sixty-seven".