1296123899 has 32 divisors (see below), whose sum is σ = 1571733504. Its totient is φ = 1044933120.

The previous prime is 1296123847. The next prime is 1296123901. The reversal of 1296123899 is 9983216921.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-1296123899 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1296123839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3474677 + ... + 3475049.

It is an arithmetic number, because the mean of its divisors is an integer number (49116672).

Almost surely, 2^1296123899 is an apocalyptic number.

1296123899 is a deficient number, since it is larger than the sum of its proper divisors (275609605).

1296123899 is a wasteful number, since it uses less digits than its factorization.

1296123899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 707.

The product of its digits is 419904, while the sum is 50.

The square root of 1296123899 is about 36001.7207783184. The cubic root of 1296123899 is about 1090.3070983305.

The spelling of 1296123899 in words is "one billion, two hundred ninety-six million, one hundred twenty-three thousand, eight hundred ninety-nine".