280191271781 has 2 divisors, whose sum is σ = 280191271782. Its totient is φ = 280191271780.

The previous prime is 280191271729. The next prime is 280191271783. The reversal of 280191271781 is 187172191082.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 277871308225 + 2319963556 = 527135^2 + 48166^2 .

It is a cyclic number.

It is not a de Polignac number, because 280191271781 - 2¹⁰ = 280191270757 is a prime.

It is a super-2 number, since 2×280191271781² (a number of 24 digits) contains 22 as substring.

It is a Sophie Germain prime.

Together with 280191271783, it forms a pair of twin primes.

It is a Chen 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 (280191271783) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 140095635890 + 140095635891.

It is an arithmetic number, because the mean of its divisors is an integer number (140095635891).

Almost surely, 2^280191271781 is an apocalyptic number.

It is an amenable number.

280191271781 is a deficient number, since it is larger than the sum of its proper divisors (1).

280191271781 is an equidigital number, since it uses as much as digits as its factorization.

280191271781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 112896, while the sum is 47.

The spelling of 280191271781 in words is "two hundred eighty billion, one hundred ninety-one million, two hundred seventy-one thousand, seven hundred eighty-one".