1265112561 has 16 divisors (see below), whose sum is σ = 1697002560. Its totient is φ = 838328640.

The previous prime is 1265112553. The next prime is 1265112571. The reversal of 1265112561 is 1652115621.

It is not a de Polignac number, because 1265112561 - 2³ = 1265112553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1265112521) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 562906 + ... + 565148.

It is an arithmetic number, because the mean of its divisors is an integer number (106062660).

Almost surely, 2^1265112561 is an apocalyptic number.

It is an amenable number.

1265112561 is a deficient number, since it is larger than the sum of its proper divisors (431889999).

1265112561 is a wasteful number, since it uses less digits than its factorization.

1265112561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3296.

The product of its digits is 3600, while the sum is 30.

The square root of 1265112561 is about 35568.4208392782. The cubic root of 1265112561 is about 1081.5411698892.

The spelling of 1265112561 in words is "one billion, two hundred sixty-five million, one hundred twelve thousand, five hundred sixty-one".