7861221701 has 2 divisors, whose sum is σ = 7861221702. Its totient is φ = 7861221700.

The previous prime is 7861221679. The next prime is 7861221703. The reversal of 7861221701 is 1071221687.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6336319201 + 1524902500 = 79601^2 + 39050^2 .

It is an emirp because it is prime and its reverse (1071221687) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7861221701 - 2¹⁰ = 7861220677 is a prime.

It is a Sophie Germain prime.

Together with 7861221703, it forms a pair of twin primes.

It is a Chen 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 (7861221703) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3930610850 + 3930610851.

It is an arithmetic number, because the mean of its divisors is an integer number (3930610851).

Almost surely, 2^7861221701 is an apocalyptic number.

It is an amenable number.

7861221701 is a deficient number, since it is larger than the sum of its proper divisors (1).

7861221701 is an equidigital number, since it uses as much as digits as its factorization.

7861221701 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9408, while the sum is 35.

The square root of 7861221701 is about 88663.5308399119. The cubic root of 7861221701 is about 1988.3676167470.

The spelling of 7861221701 in words is "seven billion, eight hundred sixty-one million, two hundred twenty-one thousand, seven hundred one".