491974537 has 2 divisors, whose sum is σ = 491974538. Its totient is φ = 491974536.

The previous prime is 491974529. The next prime is 491974559. The reversal of 491974537 is 735479194.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 319551376 + 172423161 = 17876^2 + 13131^2 .

It is a cyclic number.

It is not a de Polignac number, because 491974537 - 2³ = 491974529 is a prime.

It is equal to p_25954897 and since 491974537 and 25954897 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (491974837) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245987268 + 245987269.

It is an arithmetic number, because the mean of its divisors is an integer number (245987269).

Almost surely, 2^491974537 is an apocalyptic number.

It is an amenable number.

491974537 is a deficient number, since it is larger than the sum of its proper divisors (1).

491974537 is an equidigital number, since it uses as much as digits as its factorization.

491974537 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 952560, while the sum is 49.

The square root of 491974537 is about 22180.4990250445. The cubic root of 491974537 is about 789.4310580715.

The spelling of 491974537 in words is "four hundred ninety-one million, nine hundred seventy-four thousand, five hundred thirty-seven".