1340666881 has 2 divisors, whose sum is σ = 1340666882. Its totient is φ = 1340666880.

The previous prime is 1340666867. The next prime is 1340666911. The reversal of 1340666881 is 1886660431.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 741200625 + 599466256 = 27225^2 + 24484^2 .

It is an emirp because it is prime and its reverse (1886660431) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1340666881 - 2⁷ = 1340666753 is a prime.

It is a super-2 number, since 2×1340666881² = 3594775371620536322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1340666081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 670333440 + 670333441.

It is an arithmetic number, because the mean of its divisors is an integer number (670333441).

Almost surely, 2^1340666881 is an apocalyptic number.

It is an amenable number.

1340666881 is a deficient number, since it is larger than the sum of its proper divisors (1).

1340666881 is an equidigital number, since it uses as much as digits as its factorization.

1340666881 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 165888, while the sum is 43.

The square root of 1340666881 is about 36615.1182027315. The cubic root of 1340666881 is about 1102.6566313698.

The spelling of 1340666881 in words is "one billion, three hundred forty million, six hundred sixty-six thousand, eight hundred eighty-one".