1981048013 has 4 divisors (see below), whose sum is σ = 2264054880. Its totient is φ = 1698041148.

The previous prime is 1981048007. The next prime is 1981048019. The reversal of 1981048013 is 3108401891.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 3108401891 = 7 ⋅444057413.

It is an interprime number because it is at equal distance from previous prime (1981048007) and next prime (1981048019).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1981048013 is a prime.

It is a super-2 number, since 2×1981048013² = 7849102459622496338, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1981048019) 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, 141503423 + ... + 141503436.

It is an arithmetic number, because the mean of its divisors is an integer number (566013720).

Almost surely, 2^1981048013 is an apocalyptic number.

It is an amenable number.

1981048013 is a deficient number, since it is larger than the sum of its proper divisors (283006867).

1981048013 is an equidigital number, since it uses as much as digits as its factorization.

1981048013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 283006866.

The product of its (nonzero) digits is 6912, while the sum is 35.

The square root of 1981048013 is about 44508.9655350470. The cubic root of 1981048013 is about 1255.9287449688.

The spelling of 1981048013 in words is "one billion, nine hundred eighty-one million, forty-eight thousand, thirteen".