491375757637 has 2 divisors, whose sum is σ = 491375757638. Its totient is φ = 491375757636.

The previous prime is 491375757599. The next prime is 491375757689. The reversal of 491375757637 is 736757573194.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 463421924001 + 27953833636 = 680751^2 + 167194^2 .

It is a cyclic number.

It is not a de Polignac number, because 491375757637 - 2¹¹ = 491375755589 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (491375557637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245687878818 + 245687878819.

It is an arithmetic number, because the mean of its divisors is an integer number (245687878819).

Almost surely, 2^491375757637 is an apocalyptic number.

It is an amenable number.

491375757637 is a deficient number, since it is larger than the sum of its proper divisors (1).

491375757637 is an equidigital number, since it uses as much as digits as its factorization.

491375757637 is an evil number, because the sum of its binary digits is even.

The product of its digits is 116688600, while the sum is 64.

The spelling of 491375757637 in words is "four hundred ninety-one billion, three hundred seventy-five million, seven hundred fifty-seven thousand, six hundred thirty-seven".