3870216661 has 2 divisors, whose sum is σ = 3870216662. Its totient is φ = 3870216660.

The previous prime is 3870216611. The next prime is 3870216667. The reversal of 3870216661 is 1666120783.

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., 1950900561 + 1919316100 = 44169^2 + 43810^2 .

It is a cyclic number.

It is not a de Polignac number, because 3870216661 - 2¹³ = 3870208469 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3870216667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1935108330 + 1935108331.

It is an arithmetic number, because the mean of its divisors is an integer number (1935108331).

Almost surely, 2^3870216661 is an apocalyptic number.

It is an amenable number.

3870216661 is a deficient number, since it is larger than the sum of its proper divisors (1).

3870216661 is an equidigital number, since it uses as much as digits as its factorization.

3870216661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72576, while the sum is 40.

The square root of 3870216661 is about 62211.0654224793. The cubic root of 3870216661 is about 1570.0437681011.

The spelling of 3870216661 in words is "three billion, eight hundred seventy million, two hundred sixteen thousand, six hundred sixty-one".