1257931 has 2 divisors, whose sum is σ = 1257932. Its totient is φ = 1257930.

The previous prime is 1257911. The next prime is 1257953. The reversal of 1257931 is 1397521.

It is a weak prime.

It is an emirp because it is prime and its reverse (1397521) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1257931 - 2¹³ = 1249739 is a prime.

It is a super-2 number, since 2×1257931² = 3164780801522, which contains 22 as substring.

1257931 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 1257931.

It is not a weakly prime, because it can be changed into another prime (1257911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 628965 + 628966.

It is an arithmetic number, because the mean of its divisors is an integer number (628966).

2^1257931 is an apocalyptic number.

1257931 is a deficient number, since it is larger than the sum of its proper divisors (1).

1257931 is an equidigital number, since it uses as much as digits as its factorization.

1257931 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1890, while the sum is 28.

The square root of 1257931 is about 1121.5752315382. The cubic root of 1257931 is about 107.9490786467.

The spelling of 1257931 in words is "one million, two hundred fifty-seven thousand, nine hundred thirty-one".