381111979 has 2 divisors, whose sum is σ = 381111980. Its totient is φ = 381111978.

The previous prime is 381111977. The next prime is 381111989. The reversal of 381111979 is 979111183.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 381111979 - 2¹ = 381111977 is a prime.

Together with 381111977, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (381111977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 190555989 + 190555990.

It is an arithmetic number, because the mean of its divisors is an integer number (190555990).

Almost surely, 2^381111979 is an apocalyptic number.

381111979 is a deficient number, since it is larger than the sum of its proper divisors (1).

381111979 is an equidigital number, since it uses as much as digits as its factorization.

381111979 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13608, while the sum is 40.

The square root of 381111979 is about 19522.0895141888. The cubic root of 381111979 is about 725.0214684091.

The spelling of 381111979 in words is "three hundred eighty-one million, one hundred eleven thousand, nine hundred seventy-nine".