491174428777 has 2 divisors, whose sum is σ = 491174428778. Its totient is φ = 491174428776.

The previous prime is 491174428763. The next prime is 491174428841. The reversal of 491174428777 is 777824471194.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 265450617961 + 225723810816 = 515219^2 + 475104^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-491174428777 is a prime.

It is not a weakly prime, because it can be changed into another prime (491174428727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245587214388 + 245587214389.

It is an arithmetic number, because the mean of its divisors is an integer number (245587214389).

Almost surely, 2^491174428777 is an apocalyptic number.

It is an amenable number.

491174428777 is a deficient number, since it is larger than the sum of its proper divisors (1).

491174428777 is an equidigital number, since it uses as much as digits as its factorization.

491174428777 is an evil number, because the sum of its binary digits is even.

The product of its digits is 22127616, while the sum is 61.

The spelling of 491174428777 in words is "four hundred ninety-one billion, one hundred seventy-four million, four hundred twenty-eight thousand, seven hundred seventy-seven".