1663198761 has 8 divisors (see below), whose sum is σ = 2534398144. Its totient is φ = 950399280.

The previous prime is 1663198753. The next prime is 1663198787. The reversal of 1663198761 is 1678913661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1663198761 - 2³ = 1663198753 is a prime.

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 1663198761.

It is not an unprimeable number, because it can be changed into a prime (1663198751) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39599950 + ... + 39599991.

It is an arithmetic number, because the mean of its divisors is an integer number (316799768).

Almost surely, 2^1663198761 is an apocalyptic number.

It is an amenable number.

1663198761 is a deficient number, since it is larger than the sum of its proper divisors (871199383).

1663198761 is an equidigital number, since it uses as much as digits as its factorization.

1663198761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79199951.

The product of its digits is 326592, while the sum is 48.

The square root of 1663198761 is about 40782.3339327214. Note that the first 3 decimals coincide. The cubic root of 1663198761 is about 1184.8081991199.

The spelling of 1663198761 in words is "one billion, six hundred sixty-three million, one hundred ninety-eight thousand, seven hundred sixty-one".