1818561 has 8 divisors (see below), whose sum is σ = 2508480. Its totient is φ = 1170512.

The previous prime is 1818559. The next prime is 1818569. The reversal of 1818561 is 1658181.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1818561 - 2¹ = 1818559 is a prime.

It is a super-2 number, since 2×1818561² = 6614328221442, which contains 22 as substring.

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

It is not an unprimeable number, because it can be changed into a prime (1818569) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10365 + ... + 10538.

It is an arithmetic number, because the mean of its divisors is an integer number (313560).

2^1818561 is an apocalyptic number.

It is an amenable number.

1818561 is a deficient number, since it is larger than the sum of its proper divisors (689919).

1818561 is a wasteful number, since it uses less digits than its factorization.

1818561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20935.

The product of its digits is 1920, while the sum is 30.

The square root of 1818561 is about 1348.5403219778. The cubic root of 1818561 is about 122.0607285225.

The spelling of 1818561 in words is "one million, eight hundred eighteen thousand, five hundred sixty-one".