378959981 has 2 divisors, whose sum is σ = 378959982. Its totient is φ = 378959980.

The previous prime is 378959831. The next prime is 378960059. The reversal of 378959981 is 189959873.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 317196100 + 61763881 = 17810^2 + 7859^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-378959981 is a prime.

It is a super-2 number, since 2×378959981² = 287221334399040722, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 378959981.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (378959081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 189479990 + 189479991.

It is an arithmetic number, because the mean of its divisors is an integer number (189479991).

Almost surely, 2^378959981 is an apocalyptic number.

It is an amenable number.

378959981 is a deficient number, since it is larger than the sum of its proper divisors (1).

378959981 is an equidigital number, since it uses as much as digits as its factorization.

378959981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4898880, while the sum is 59.

The square root of 378959981 is about 19466.8944878221. The cubic root of 378959981 is about 723.6542493315.

The spelling of 378959981 in words is "three hundred seventy-eight million, nine hundred fifty-nine thousand, nine hundred eighty-one".