291745954781 has 2 divisors, whose sum is σ = 291745954782. Its totient is φ = 291745954780.

The previous prime is 291745954777. The next prime is 291745954793. The reversal of 291745954781 is 187459547192.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 268229732281 + 23516222500 = 517909^2 + 153350^2 .

It is a cyclic number.

It is not a de Polignac number, because 291745954781 - 2² = 291745954777 is a prime.

It is a super-2 number, since 2×291745954781² (a number of 24 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (291745954741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 145872977390 + 145872977391.

It is an arithmetic number, because the mean of its divisors is an integer number (145872977391).

Almost surely, 2^291745954781 is an apocalyptic number.

It is an amenable number.

291745954781 is a deficient number, since it is larger than the sum of its proper divisors (1).

291745954781 is an equidigital number, since it uses as much as digits as its factorization.

291745954781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 25401600, while the sum is 62.

The spelling of 291745954781 in words is "two hundred ninety-one billion, seven hundred forty-five million, nine hundred fifty-four thousand, seven hundred eighty-one".