1021281257 has 2 divisors, whose sum is σ = 1021281258. Its totient is φ = 1021281256.

The previous prime is 1021281241. The next prime is 1021281343. The reversal of 1021281257 is 7521821201.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 871194256 + 150087001 = 29516^2 + 12251^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021281257 - 2⁴ = 1021281241 is a prime.

It is not a weakly prime, because it can be changed into another prime (1021281557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510640628 + 510640629.

It is an arithmetic number, because the mean of its divisors is an integer number (510640629).

Almost surely, 2^1021281257 is an apocalyptic number.

It is an amenable number.

1021281257 is a deficient number, since it is larger than the sum of its proper divisors (1).

1021281257 is an equidigital number, since it uses as much as digits as its factorization.

1021281257 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2240, while the sum is 29.

The square root of 1021281257 is about 31957.4914065544. The cubic root of 1021281257 is about 1007.0440176450.

The spelling of 1021281257 in words is "one billion, twenty-one million, two hundred eighty-one thousand, two hundred fifty-seven".