1836394561 has 4 divisors (see below), whose sum is σ = 1837253632. Its totient is φ = 1835535492.

The previous prime is 1836394541. The next prime is 1836394601. The reversal of 1836394561 is 1654936381.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1836394561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1836394531) 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, 426321 + ... + 430606.

It is an arithmetic number, because the mean of its divisors is an integer number (459313408).

Almost surely, 2^1836394561 is an apocalyptic number.

It is an amenable number.

1836394561 is a deficient number, since it is larger than the sum of its proper divisors (859071).

1836394561 is an equidigital number, since it uses as much as digits as its factorization.

1836394561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 859070.

The product of its digits is 466560, while the sum is 46.

The square root of 1836394561 is about 42853.1744565091. The cubic root of 1836394561 is about 1224.5842400833.

The spelling of 1836394561 in words is "one billion, eight hundred thirty-six million, three hundred ninety-four thousand, five hundred sixty-one".