1998636941 has 6 divisors (see below), whose sum is σ = 2324945070. Its totient is φ = 1713117336.

The previous prime is 1998636931. The next prime is 1998637009. The reversal of 1998636941 is 1496368991.

It can be written as a sum of positive squares in only one way, i.e., 1973936041 + 24700900 = 44429^2 + 4970^2 .

It is not a de Polignac number, because 1998636941 - 2¹⁴ = 1998620557 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1998636931) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 20394206 + ... + 20394303.

It is an arithmetic number, because the mean of its divisors is an integer number (387490845).

Almost surely, 2^1998636941 is an apocalyptic number.

It is an amenable number.

1998636941 is a deficient number, since it is larger than the sum of its proper divisors (326308129).

1998636941 is an equidigital number, since it uses as much as digits as its factorization.

1998636941 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40788523 (or 40788516 counting only the distinct ones).

The product of its digits is 2519424, while the sum is 56.

The square root of 1998636941 is about 44706.1174896680. The cubic root of 1998636941 is about 1259.6347603924.

The spelling of 1998636941 in words is "one billion, nine hundred ninety-eight million, six hundred thirty-six thousand, nine hundred forty-one".