1878561 has 6 divisors (see below), whose sum is σ = 2713490. Its totient is φ = 1252368.

The previous prime is 1878559. The next prime is 1878563. The reversal of 1878561 is 1658781.

It is an interprime number because it is at equal distance from previous prime (1878559) and next prime (1878563).

It can be written as a sum of positive squares in only one way, i.e., 1742400 + 136161 = 1320^2 + 369^2 .

It is not a de Polignac number, because 1878561 - 2¹ = 1878559 is a prime.

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

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1878563) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 104356 + ... + 104373.

2^1878561 is an apocalyptic number.

It is an amenable number.

1878561 is a deficient number, since it is larger than the sum of its proper divisors (834929).

1878561 is a wasteful number, since it uses less digits than its factorization.

1878561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 208735 (or 208732 counting only the distinct ones).

The product of its digits is 13440, while the sum is 36.

The square root of 1878561 is about 1370.6060703207. The cubic root of 1878561 is about 123.3886181818.

The spelling of 1878561 in words is "one million, eight hundred seventy-eight thousand, five hundred sixty-one".