1281973313 has 4 divisors (see below), whose sum is σ = 1293954480. Its totient is φ = 1269992148.

The previous prime is 1281973309. The next prime is 1281973331. The reversal of 1281973313 is 3133791821.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1281973313 - 2² = 1281973309 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1281973613) 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 3 ways as a sum of consecutive naturals, for example, 5990423 + ... + 5990636.

It is an arithmetic number, because the mean of its divisors is an integer number (323488620).

Almost surely, 2^1281973313 is an apocalyptic number.

It is an amenable number.

1281973313 is a deficient number, since it is larger than the sum of its proper divisors (11981167).

1281973313 is a wasteful number, since it uses less digits than its factorization.

1281973313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11981166.

The product of its digits is 27216, while the sum is 38.

The square root of 1281973313 is about 35804.6549068693. The cubic root of 1281973313 is about 1086.3247180298.

The spelling of 1281973313 in words is "one billion, two hundred eighty-one million, nine hundred seventy-three thousand, three hundred thirteen".