1878641 has 2 divisors, whose sum is σ = 1878642. Its totient is φ = 1878640.

The previous prime is 1878629. The next prime is 1878659. The reversal of 1878641 is 1468781.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1449616 + 429025 = 1204^2 + 655^2 .

It is an emirp because it is prime and its reverse (1468781) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1878641 - 2⁶ = 1878577 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1878841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 939320 + 939321.

It is an arithmetic number, because the mean of its divisors is an integer number (939321).

2^1878641 is an apocalyptic number.

It is an amenable number.

1878641 is a deficient number, since it is larger than the sum of its proper divisors (1).

1878641 is an equidigital number, since it uses as much as digits as its factorization.

1878641 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10752, while the sum is 35.

The square root of 1878641 is about 1370.6352541796. The cubic root of 1878641 is about 123.3903696908.

The spelling of 1878641 in words is "one million, eight hundred seventy-eight thousand, six hundred forty-one".