3978241758209 has 2 divisors, whose sum is σ = 3978241758210. Its totient is φ = 3978241758208.

The previous prime is 3978241758191. The next prime is 3978241758223. The reversal of 3978241758209 is 9028571428793.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3481780598209 + 496461160000 = 1865953^2 + 704600^2 .

It is a cyclic number.

It is not a de Polignac number, because 3978241758209 - 2²⁰ = 3978240709633 is a prime.

It is not a weakly prime, because it can be changed into another prime (3978241758109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1989120879104 + 1989120879105.

It is an arithmetic number, because the mean of its divisors is an integer number (1989120879105).

Almost surely, 2^{3978241758209} is an apocalyptic number.

It is an amenable number.

3978241758209 is a deficient number, since it is larger than the sum of its proper divisors (1).

3978241758209 is an equidigital number, since it uses as much as digits as its factorization.

3978241758209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 60963840, while the sum is 65.

The spelling of 3978241758209 in words is "three trillion, nine hundred seventy-eight billion, two hundred forty-one million, seven hundred fifty-eight thousand, two hundred nine".