1913347661 has 2 divisors, whose sum is σ = 1913347662. Its totient is φ = 1913347660.

The previous prime is 1913347619. The next prime is 1913347669. The reversal of 1913347661 is 1667433191.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1909165636 + 4182025 = 43694^2 + 2045^2 .

It is a cyclic number.

It is not a de Polignac number, because 1913347661 - 2²² = 1909153357 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1913347669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 956673830 + 956673831.

It is an arithmetic number, because the mean of its divisors is an integer number (956673831).

Almost surely, 2^1913347661 is an apocalyptic number.

It is an amenable number.

1913347661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1913347661 is an equidigital number, since it uses as much as digits as its factorization.

1913347661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 81648, while the sum is 41.

The square root of 1913347661 is about 43741.8296485184. The cubic root of 1913347661 is about 1241.4558994194.

The spelling of 1913347661 in words is "one billion, nine hundred thirteen million, three hundred forty-seven thousand, six hundred sixty-one".