391793040493 has 2 divisors, whose sum is σ = 391793040494. Its totient is φ = 391793040492.

The previous prime is 391793040491. The next prime is 391793040571. The reversal of 391793040493 is 394040397193.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 320812358409 + 70980682084 = 566403^2 + 266422^2 .

It is a cyclic number.

It is not a de Polignac number, because 391793040493 - 2¹ = 391793040491 is a prime.

Together with 391793040491, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 391793040493.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (391793040491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 195896520246 + 195896520247.

It is an arithmetic number, because the mean of its divisors is an integer number (195896520247).

Almost surely, 2^391793040493 is an apocalyptic number.

It is an amenable number.

391793040493 is a deficient number, since it is larger than the sum of its proper divisors (1).

391793040493 is an equidigital number, since it uses as much as digits as its factorization.

391793040493 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2204496, while the sum is 52.

The spelling of 391793040493 in words is "three hundred ninety-one billion, seven hundred ninety-three million, forty thousand, four hundred ninety-three".