281256491 has 2 divisors, whose sum is σ = 281256492. Its totient is φ = 281256490.

The previous prime is 281256467. The next prime is 281256523. The reversal of 281256491 is 194652182.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 281256491 - 2⁶ = 281256427 is a prime.

It is not a weakly prime, because it can be changed into another prime (281256401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 140628245 + 140628246.

It is an arithmetic number, because the mean of its divisors is an integer number (140628246).

Almost surely, 2^281256491 is an apocalyptic number.

281256491 is a deficient number, since it is larger than the sum of its proper divisors (1).

281256491 is an equidigital number, since it uses as much as digits as its factorization.

281256491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34560, while the sum is 38.

The square root of 281256491 is about 16770.7033543617. The cubic root of 281256491 is about 655.1903888786.

The spelling of 281256491 in words is "two hundred eighty-one million, two hundred fifty-six thousand, four hundred ninety-one".