491918824093 has 2 divisors, whose sum is σ = 491918824094. Its totient is φ = 491918824092.

The previous prime is 491918824049. The next prime is 491918824127. The reversal of 491918824093 is 390428819194.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 482362197529 + 9556626564 = 694523^2 + 97758^2 .

It is a cyclic number.

It is not a de Polignac number, because 491918824093 - 2¹³ = 491918815901 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (491918824393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245959412046 + 245959412047.

It is an arithmetic number, because the mean of its divisors is an integer number (245959412047).

Almost surely, 2^491918824093 is an apocalyptic number.

It is an amenable number.

491918824093 is a deficient number, since it is larger than the sum of its proper divisors (1).

491918824093 is an equidigital number, since it uses as much as digits as its factorization.

491918824093 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4478976, while the sum is 58.

The spelling of 491918824093 in words is "four hundred ninety-one billion, nine hundred eighteen million, eight hundred twenty-four thousand, ninety-three".