1261444291 has 8 divisors (see below), whose sum is σ = 1323324000. Its totient is φ = 1200790080.

The previous prime is 1261444243. The next prime is 1261444313. The reversal of 1261444291 is 1924441621.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1261444291 - 2⁹ = 1261443779 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1261444241) 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 7 ways as a sum of consecutive naturals, for example, 304266 + ... + 308383.

It is an arithmetic number, because the mean of its divisors is an integer number (165415500).

Almost surely, 2^1261444291 is an apocalyptic number.

1261444291 is a deficient number, since it is larger than the sum of its proper divisors (61879709).

1261444291 is an equidigital number, since it uses as much as digits as its factorization.

1261444291 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 612749.

The product of its digits is 13824, while the sum is 34.

The square root of 1261444291 is about 35516.8170167317. The cubic root of 1261444291 is about 1080.4948266900.

The spelling of 1261444291 in words is "one billion, two hundred sixty-one million, four hundred forty-four thousand, two hundred ninety-one".