1243255871 has 8 divisors (see below), whose sum is σ = 1460608464. Its totient is φ = 1043291520.

The previous prime is 1243255843. The next prime is 1243255879. The reversal of 1243255871 is 1785523421.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1243255871 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1243255879) 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, 4346906 + ... + 4347191.

It is an arithmetic number, because the mean of its divisors is an integer number (182576058).

Almost surely, 2^1243255871 is an apocalyptic number.

1243255871 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1243255871 is a deficient number, since it is larger than the sum of its proper divisors (217352593).

1243255871 is a wasteful number, since it uses less digits than its factorization.

1243255871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8694121.

The product of its digits is 67200, while the sum is 38.

The square root of 1243255871 is about 35259.8336779968. The cubic root of 1243255871 is about 1075.2765456900.

The spelling of 1243255871 in words is "one billion, two hundred forty-three million, two hundred fifty-five thousand, eight hundred seventy-one".