7991020013 has 2 divisors, whose sum is σ = 7991020014. Its totient is φ = 7991020012.

The previous prime is 7991020001. The next prime is 7991020027. The reversal of 7991020013 is 3100201997.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6409923844 + 1581096169 = 80062^2 + 39763^2 .

It is an emirp because it is prime and its reverse (3100201997) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7991020013 - 2⁴ = 7991019997 is a prime.

It is a super-3 number, since 3×7991020013³ (a number of 31 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7991020073) 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 as a sum of consecutive naturals, namely, 3995510006 + 3995510007.

It is an arithmetic number, because the mean of its divisors is an integer number (3995510007).

Almost surely, 2^7991020013 is an apocalyptic number.

It is an amenable number.

7991020013 is a deficient number, since it is larger than the sum of its proper divisors (1).

7991020013 is an equidigital number, since it uses as much as digits as its factorization.

7991020013 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3402, while the sum is 32.

The square root of 7991020013 is about 89392.5053513996. The cubic root of 7991020013 is about 1999.2513875747.

The spelling of 7991020013 in words is "seven billion, nine hundred ninety-one million, twenty thousand, thirteen".