1261014561 has 20 divisors (see below), whose sum is σ = 1884703744. Its totient is φ = 840245400.

The previous prime is 1261014541. The next prime is 1261014589. The reversal of 1261014561 is 1654101621.

1261014561 is a `hidden beast` number, since 1 + 2 + 610 + 1 + 45 + 6 + 1 = 666.

It is not a de Polignac number, because 1261014561 - 2⁵ = 1261014529 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1261014541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 272376 + ... + 276966.

Almost surely, 2^1261014561 is an apocalyptic number.

It is an amenable number.

1261014561 is a deficient number, since it is larger than the sum of its proper divisors (623689183).

1261014561 is an equidigital number, since it uses as much as digits as its factorization.

1261014561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7994 (or 7985 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 1261014561 is about 35510.7668320469. The cubic root of 1261014561 is about 1080.3721171416.

The spelling of 1261014561 in words is "one billion, two hundred sixty-one million, fourteen thousand, five hundred sixty-one".