491626908613 has 2 divisors, whose sum is σ = 491626908614. Its totient is φ = 491626908612.

The previous prime is 491626908601. The next prime is 491626908653. The reversal of 491626908613 is 316809626194.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 430589253249 + 61037655364 = 656193^2 + 247058^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-491626908613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (491626908653) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245813454306 + 245813454307.

It is an arithmetic number, because the mean of its divisors is an integer number (245813454307).

Almost surely, 2^491626908613 is an apocalyptic number.

It is an amenable number.

491626908613 is a deficient number, since it is larger than the sum of its proper divisors (1).

491626908613 is an equidigital number, since it uses as much as digits as its factorization.

491626908613 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3359232, while the sum is 55.

The spelling of 491626908613 in words is "four hundred ninety-one billion, six hundred twenty-six million, nine hundred eight thousand, six hundred thirteen".