1263561 has 16 divisors (see below), whose sum is σ = 1834560. Its totient is φ = 768960.

The previous prime is 1263547. The next prime is 1263569. The reversal of 1263561 is 1653621.

It is not a de Polignac number, because 1263561 - 2¹⁴ = 1247177 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1263569) 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 in 15 ways as a sum of consecutive naturals, for example, 6891 + ... + 7071.

It is an arithmetic number, because the mean of its divisors is an integer number (114660).

2^1263561 is an apocalyptic number.

It is an amenable number.

1263561 is a deficient number, since it is larger than the sum of its proper divisors (570999).

1263561 is a wasteful number, since it uses less digits than its factorization.

1263561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 376.

The product of its digits is 1080, while the sum is 24.

The square root of 1263561 is about 1124.0822923612. The cubic root of 1263561 is about 108.1098847304.

The spelling of 1263561 in words is "one million, two hundred sixty-three thousand, five hundred sixty-one".