1864561 has 4 divisors (see below), whose sum is σ = 1883124. Its totient is φ = 1846000.

The previous prime is 1864559. The next prime is 1864567. The reversal of 1864561 is 1654681.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 950625 + 913936 = 975^2 + 956^2 .

It is a cyclic number.

It is not a de Polignac number, because 1864561 - 2¹ = 1864559 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1864567) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9130 + ... + 9331.

It is an arithmetic number, because the mean of its divisors is an integer number (470781).

2^1864561 is an apocalyptic number.

It is an amenable number.

1864561 is a deficient number, since it is larger than the sum of its proper divisors (18563).

1864561 is a wasteful number, since it uses less digits than its factorization.

1864561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18562.

The product of its digits is 5760, while the sum is 31.

The square root of 1864561 is about 1365.4892895955. The cubic root of 1864561 is about 123.0813351483.

The spelling of 1864561 in words is "one million, eight hundred sixty-four thousand, five hundred sixty-one".