998779013 has 2 divisors, whose sum is σ = 998779014. Its totient is φ = 998779012.

The previous prime is 998779003. The next prime is 998779031. The reversal of 998779013 is 310977899.

Together with next prime (998779031) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 967396609 + 31382404 = 31103^2 + 5602^2 .

It is a cyclic number.

It is not a de Polignac number, because 998779013 - 2¹⁴ = 998762629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (998779003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499389506 + 499389507.

It is an arithmetic number, because the mean of its divisors is an integer number (499389507).

Almost surely, 2^998779013 is an apocalyptic number.

It is an amenable number.

998779013 is a deficient number, since it is larger than the sum of its proper divisors (1).

998779013 is an equidigital number, since it uses as much as digits as its factorization.

998779013 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 857304, while the sum is 53.

The square root of 998779013 is about 31603.4652055752. The cubic root of 998779013 is about 999.5928385754.

The spelling of 998779013 in words is "nine hundred ninety-eight million, seven hundred seventy-nine thousand, thirteen".