3981609979 has 2 divisors, whose sum is σ = 3981609980. Its totient is φ = 3981609978.

The previous prime is 3981609977. The next prime is 3981610007. The reversal of 3981609979 is 9799061893.

It is a weak prime.

It is an emirp because it is prime and its reverse (9799061893) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3981609979 - 2¹ = 3981609977 is a prime.

Together with 3981609977, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (3981609977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1990804989 + 1990804990.

It is an arithmetic number, because the mean of its divisors is an integer number (1990804990).

Almost surely, 2^3981609979 is an apocalyptic number.

3981609979 is a deficient number, since it is larger than the sum of its proper divisors (1).

3981609979 is an equidigital number, since it uses as much as digits as its factorization.

3981609979 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6613488, while the sum is 61.

The square root of 3981609979 is about 63099.9998335975. Note that the first 3 decimals coincide. The cubic root of 3981609979 is about 1584.9646194174.

The spelling of 3981609979 in words is "three billion, nine hundred eighty-one million, six hundred nine thousand, nine hundred seventy-nine".