1263408561 has 12 divisors (see below), whose sum is σ = 1904268288. Its totient is φ = 805651704.

The previous prime is 1263408547. The next prime is 1263408569. The reversal of 1263408561 is 1658043621.

It is a happy number.

1263408561 is a `hidden beast` number, since 12 + 634 + 0 + 8 + 5 + 6 + 1 = 666.

It is not a de Polignac number, because 1263408561 - 2⁵ = 1263408529 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1263408569) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3051505 + ... + 3051918.

It is an arithmetic number, because the mean of its divisors is an integer number (158689024).

Almost surely, 2^1263408561 is an apocalyptic number.

It is an amenable number.

1263408561 is a deficient number, since it is larger than the sum of its proper divisors (640859727).

1263408561 is a wasteful number, since it uses less digits than its factorization.

1263408561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6103452 (or 6103449 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 1263408561 is about 35544.4589352546. The cubic root of 1263408561 is about 1081.0553701111.

The spelling of 1263408561 in words is "one billion, two hundred sixty-three million, four hundred eight thousand, five hundred sixty-one".