1257540 has 24 divisors (see below), whose sum is σ = 3521280. Its totient is φ = 335328.

The previous prime is 1257521. The next prime is 1257547. The reversal of 1257540 is 457521.

It is a self number, because there is not a number n which added to its sum of digits gives 1257540.

It is not an unprimeable number, because it can be changed into a prime (1257547) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10420 + ... + 10539.

It is an arithmetic number, because the mean of its divisors is an integer number (146720).

2^1257540 is an apocalyptic number.

1257540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1257540 is an abundant number, since it is smaller than the sum of its proper divisors (2263740).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1257540 is a wasteful number, since it uses less digits than its factorization.

1257540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20971 (or 20969 counting only the distinct ones).

The product of its (nonzero) digits is 1400, while the sum is 24.

The square root of 1257540 is about 1121.4009095769. The cubic root of 1257540 is about 107.9378929607.

The spelling of 1257540 in words is "one million, two hundred fifty-seven thousand, five hundred forty".