1261543 has 8 divisors (see below), whose sum is σ = 1349120. Its totient is φ = 1176120.

The previous prime is 1261531. The next prime is 1261549. The reversal of 1261543 is 3451621.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1261543 - 2¹⁷ = 1130471 is a prime.

It is a Duffinian number.

1261543 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1261549) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 778 + ... + 1768.

It is an arithmetic number, because the mean of its divisors is an integer number (168640).

2^1261543 is an apocalyptic number.

1261543 is a deficient number, since it is larger than the sum of its proper divisors (87577).

1261543 is an equidigital number, since it uses as much as digits as its factorization.

1261543 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1077.

The product of its digits is 720, while the sum is 22.

The square root of 1261543 is about 1123.1843125685. The cubic root of 1261543 is about 108.0523009143.

The spelling of 1261543 in words is "one million, two hundred sixty-one thousand, five hundred forty-three".