7855237661 has 2 divisors, whose sum is σ = 7855237662. Its totient is φ = 7855237660.

The previous prime is 7855237613. The next prime is 7855237673. The reversal of 7855237661 is 1667325587.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7082064025 + 773173636 = 84155^2 + 27806^2 .

It is a cyclic number.

It is not a de Polignac number, because 7855237661 - 2⁶ = 7855237597 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7855237681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3927618830 + 3927618831.

It is an arithmetic number, because the mean of its divisors is an integer number (3927618831).

Almost surely, 2^7855237661 is an apocalyptic number.

It is an amenable number.

7855237661 is a deficient number, since it is larger than the sum of its proper divisors (1).

7855237661 is an equidigital number, since it uses as much as digits as its factorization.

7855237661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2116800, while the sum is 50.

The square root of 7855237661 is about 88629.7786356256. The cubic root of 7855237661 is about 1987.8629669542.

The spelling of 7855237661 in words is "seven billion, eight hundred fifty-five million, two hundred thirty-seven thousand, six hundred sixty-one".