1276245561 has 8 divisors (see below), whose sum is σ = 1791221920. Its totient is φ = 806049792.

The previous prime is 1276245533. The next prime is 1276245571. The reversal of 1276245561 is 1655426721.

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

It is not a de Polignac number, because 1276245561 - 2⁹ = 1276245049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1276245571) 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, 11195080 + ... + 11195193.

It is an arithmetic number, because the mean of its divisors is an integer number (223902740).

Almost surely, 2^1276245561 is an apocalyptic number.

It is an amenable number.

1276245561 is a deficient number, since it is larger than the sum of its proper divisors (514976359).

1276245561 is a wasteful number, since it uses less digits than its factorization.

1276245561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22390295.

The product of its digits is 100800, while the sum is 39.

The square root of 1276245561 is about 35724.5792277530. The cubic root of 1276245561 is about 1084.7044325054.

The spelling of 1276245561 in words is "one billion, two hundred seventy-six million, two hundred forty-five thousand, five hundred sixty-one".