1276311921 has 16 divisors (see below), whose sum is σ = 1735883136. Its totient is φ = 833845376.

The previous prime is 1276311899. The next prime is 1276311923. The reversal of 1276311921 is 1291136721.

It is a cyclic number.

It is not a de Polignac number, because 1276311921 - 2⁹ = 1276311409 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1276311923) 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, 147316 + ... + 155738.

It is an arithmetic number, because the mean of its divisors is an integer number (108492696).

Almost surely, 2^1276311921 is an apocalyptic number.

It is an amenable number.

1276311921 is a deficient number, since it is larger than the sum of its proper divisors (459571215).

1276311921 is an equidigital number, since it uses as much as digits as its factorization.

1276311921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9432.

The product of its digits is 4536, while the sum is 33.

The square root of 1276311921 is about 35725.5079879909. The cubic root of 1276311921 is about 1084.7232323719.

The spelling of 1276311921 in words is "one billion, two hundred seventy-six million, three hundred eleven thousand, nine hundred twenty-one".