1257970561 has 2 divisors, whose sum is σ = 1257970562. Its totient is φ = 1257970560.

The previous prime is 1257970543. The next prime is 1257970577. The reversal of 1257970561 is 1650797521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1113490161 + 144480400 = 33369^2 + 12020^2 .

It is a cyclic number.

It is not a de Polignac number, because 1257970561 - 2¹⁷ = 1257839489 is a prime.

It is not a weakly prime, because it can be changed into another prime (1257970501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 628985280 + 628985281.

It is an arithmetic number, because the mean of its divisors is an integer number (628985281).

Almost surely, 2^1257970561 is an apocalyptic number.

It is an amenable number.

1257970561 is a deficient number, since it is larger than the sum of its proper divisors (1).

1257970561 is an equidigital number, since it uses as much as digits as its factorization.

1257970561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 132300, while the sum is 43.

The square root of 1257970561 is about 35467.8806950740. The cubic root of 1257970561 is about 1079.5021027441.

The spelling of 1257970561 in words is "one billion, two hundred fifty-seven million, nine hundred seventy thousand, five hundred sixty-one".