3878981 has 2 divisors, whose sum is σ = 3878982. Its totient is φ = 3878980.

The previous prime is 3878947. The next prime is 3878993. The reversal of 3878981 is 1898783.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2356225 + 1522756 = 1535^2 + 1234^2 .

It is an emirp because it is prime and its reverse (1898783) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3878981 is a prime.

It is a super-2 number, since 2×3878981² = 30092987196722, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3878921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1939490 + 1939491.

It is an arithmetic number, because the mean of its divisors is an integer number (1939491).

Almost surely, 2^3878981 is an apocalyptic number.

It is an amenable number.

3878981 is a deficient number, since it is larger than the sum of its proper divisors (1).

3878981 is an equidigital number, since it uses as much as digits as its factorization.

3878981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 96768, while the sum is 44.

The square root of 3878981 is about 1969.5128839386. The cubic root of 3878981 is about 157.1228027537.

The spelling of 3878981 in words is "three million, eight hundred seventy-eight thousand, nine hundred eighty-one".