1991648603 has 4 divisors (see below), whose sum is σ = 2276169840. Its totient is φ = 1707127368.

The previous prime is 1991648531. The next prime is 1991648653. The reversal of 1991648603 is 3068461991.

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 1991648603 - 2¹⁴ = 1991632219 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1991648653) 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, 142260608 + ... + 142260621.

It is an arithmetic number, because the mean of its divisors is an integer number (569042460).

Almost surely, 2^1991648603 is an apocalyptic number.

1991648603 is a deficient number, since it is larger than the sum of its proper divisors (284521237).

1991648603 is an equidigital number, since it uses as much as digits as its factorization.

1991648603 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 284521236.

The product of its (nonzero) digits is 279936, while the sum is 47.

The square root of 1991648603 is about 44627.8904161960. The cubic root of 1991648603 is about 1258.1649197859.

The spelling of 1991648603 in words is "one billion, nine hundred ninety-one million, six hundred forty-eight thousand, six hundred three".