3778861 has 2 divisors, whose sum is σ = 3778862. Its totient is φ = 3778860.

The previous prime is 3778837. The next prime is 3778897. The reversal of 3778861 is 1688773.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3496900 + 281961 = 1870^2 + 531^2 .

It is an emirp because it is prime and its reverse (1688773) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3778861 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3778661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1889430 + 1889431.

It is an arithmetic number, because the mean of its divisors is an integer number (1889431).

Almost surely, 2^3778861 is an apocalyptic number.

It is an amenable number.

3778861 is a deficient number, since it is larger than the sum of its proper divisors (1).

3778861 is an equidigital number, since it uses as much as digits as its factorization.

3778861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 56448, while the sum is 40.

The square root of 3778861 is about 1943.9292682606. The cubic root of 3778861 is about 155.7591753177.

The spelling of 3778861 in words is "three million, seven hundred seventy-eight thousand, eight hundred sixty-one".