1257257543 has 2 divisors, whose sum is σ = 1257257544. Its totient is φ = 1257257542.

The previous prime is 1257257537. The next prime is 1257257623. The reversal of 1257257543 is 3457527521.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1257257543 - 2⁴ = 1257257527 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1257257543.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1257257513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 628628771 + 628628772.

It is an arithmetic number, because the mean of its divisors is an integer number (628628772).

Almost surely, 2^1257257543 is an apocalyptic number.

1257257543 is a deficient number, since it is larger than the sum of its proper divisors (1).

1257257543 is an equidigital number, since it uses as much as digits as its factorization.

1257257543 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 294000, while the sum is 41.

The square root of 1257257543 is about 35457.8276689365. The cubic root of 1257257543 is about 1079.2981101858.

The spelling of 1257257543 in words is "one billion, two hundred fifty-seven million, two hundred fifty-seven thousand, five hundred forty-three".