491213195009 has 2 divisors, whose sum is σ = 491213195010. Its totient is φ = 491213195008.

The previous prime is 491213195003. The next prime is 491213195027. The reversal of 491213195009 is 900591312194.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 273558288784 + 217654906225 = 523028^2 + 466535^2 .

It is a cyclic number.

It is not a de Polignac number, because 491213195009 - 2¹² = 491213190913 is a prime.

It is not a weakly prime, because it can be changed into another prime (491213195003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245606597504 + 245606597505.

It is an arithmetic number, because the mean of its divisors is an integer number (245606597505).

Almost surely, 2^491213195009 is an apocalyptic number.

It is an amenable number.

491213195009 is a deficient number, since it is larger than the sum of its proper divisors (1).

491213195009 is an equidigital number, since it uses as much as digits as its factorization.

491213195009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 87480, while the sum is 44.

The spelling of 491213195009 in words is "four hundred ninety-one billion, two hundred thirteen million, one hundred ninety-five thousand, nine".