3878561 has 2 divisors, whose sum is σ = 3878562. Its totient is φ = 3878560.

The previous prime is 3878549. The next prime is 3878597. The reversal of 3878561 is 1658783.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3876961 + 1600 = 1969^2 + 40^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3878561 is a prime.

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

It is not a weakly prime, because it can be changed into another prime (3878521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1939280 + 1939281.

It is an arithmetic number, because the mean of its divisors is an integer number (1939281).

Almost surely, 2^3878561 is an apocalyptic number.

It is an amenable number.

3878561 is a deficient number, since it is larger than the sum of its proper divisors (1).

3878561 is an equidigital number, since it uses as much as digits as its factorization.

3878561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 40320, while the sum is 38.

The square root of 3878561 is about 1969.4062557025. The cubic root of 3878561 is about 157.1171316802.

The spelling of 3878561 in words is "three million, eight hundred seventy-eight thousand, five hundred sixty-one".