1296121361 has 6 divisors (see below), whose sum is σ = 1376848950. Its totient is φ = 1219878656.

The previous prime is 1296121357. The next prime is 1296121367. The reversal of 1296121361 is 1631216921.

It can be written as a sum of positive squares in 3 ways, for example, as 883218961 + 412902400 = 29719^2 + 20320^2 .

It is not a de Polignac number, because 1296121361 - 2² = 1296121357 is a prime.

It is a super-5 number, since 5×1296121361⁵ (a number of 47 digits) contains 55555 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1296121367) 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 5 ways as a sum of consecutive naturals, for example, 2242136 + ... + 2242713.

It is an arithmetic number, because the mean of its divisors is an integer number (229474825).

Almost surely, 2^1296121361 is an apocalyptic number.

It is an amenable number.

1296121361 is a deficient number, since it is larger than the sum of its proper divisors (80727589).

1296121361 is an equidigital number, since it uses as much as digits as its factorization.

1296121361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4484883 (or 4484866 counting only the distinct ones).

The product of its digits is 3888, while the sum is 32.

The square root of 1296121361 is about 36001.6855299860. The cubic root of 1296121361 is about 1090.3063866698.

The spelling of 1296121361 in words is "one billion, two hundred ninety-six million, one hundred twenty-one thousand, three hundred sixty-one".