1643498963 has 4 divisors (see below), whose sum is σ = 1643869248. Its totient is φ = 1643128680.

The previous prime is 1643498959. The next prime is 1643499023. The reversal of 1643498963 is 3698943461.

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 1643498963 - 2² = 1643498959 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1643498663) 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, 178403 + ... + 187388.

It is an arithmetic number, because the mean of its divisors is an integer number (410967312).

Almost surely, 2^1643498963 is an apocalyptic number.

1643498963 is a deficient number, since it is larger than the sum of its proper divisors (370285).

1643498963 is an equidigital number, since it uses as much as digits as its factorization.

1643498963 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 370284.

The product of its digits is 3359232, while the sum is 53.

The square root of 1643498963 is about 40540.0908114424. The cubic root of 1643498963 is about 1180.1117779299. Note that the first 3 decimals are identical.

It can be divided in two parts, 1643498 and 963, that added together give a palindrome (1644461).

The spelling of 1643498963 in words is "one billion, six hundred forty-three million, four hundred ninety-eight thousand, nine hundred sixty-three".