1257307217 has 2 divisors, whose sum is σ = 1257307218. Its totient is φ = 1257307216.

The previous prime is 1257307211. The next prime is 1257307237. The reversal of 1257307217 is 7127037521.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 654899281 + 602407936 = 25591^2 + 24544^2 .

It is a cyclic number.

It is not a de Polignac number, because 1257307217 - 2⁴ = 1257307201 is a prime.

It is not a weakly prime, because it can be changed into another prime (1257307211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 628653608 + 628653609.

It is an arithmetic number, because the mean of its divisors is an integer number (628653609).

Almost surely, 2^1257307217 is an apocalyptic number.

It is an amenable number.

1257307217 is a deficient number, since it is larger than the sum of its proper divisors (1).

1257307217 is an equidigital number, since it uses as much as digits as its factorization.

1257307217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20580, while the sum is 35.

The square root of 1257307217 is about 35458.5281279412. The cubic root of 1257307217 is about 1079.3123242844.

The spelling of 1257307217 in words is "one billion, two hundred fifty-seven million, three hundred seven thousand, two hundred seventeen".