491131594137641 has 2 divisors, whose sum is σ = 491131594137642. Its totient is φ = 491131594137640.

The previous prime is 491131594137599. The next prime is 491131594137643. The reversal of 491131594137641 is 146731495131194.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 491046586904041 + 85007233600 = 22159571^2 + 291560^2 .

It is a cyclic number.

It is not a de Polignac number, because 491131594137641 - 2¹⁴ = 491131594121257 is a prime.

Together with 491131594137643, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (491131594137643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245565797068820 + 245565797068821.

It is an arithmetic number, because the mean of its divisors is an integer number (245565797068821).

Almost surely, 2^{491131594137641} is an apocalyptic number.

It is an amenable number.

491131594137641 is a deficient number, since it is larger than the sum of its proper divisors (1).

491131594137641 is an equidigital number, since it uses as much as digits as its factorization.

491131594137641 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9797760, while the sum is 59.

The spelling of 491131594137641 in words is "four hundred ninety-one trillion, one hundred thirty-one billion, five hundred ninety-four million, one hundred thirty-seven thousand, six hundred forty-one".