1321618 has 4 divisors (see below), whose sum is σ = 1982430. Its totient is φ = 660808.

The previous prime is 1321601. The next prime is 1321627. The reversal of 1321618 is 8161231.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8161231 = 13 ⋅627787.

It can be written as a sum of positive squares in only one way, i.e., 915849 + 405769 = 957^2 + 637^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330403 + ... + 330406.

2^1321618 is an apocalyptic number.

1321618 is a deficient number, since it is larger than the sum of its proper divisors (660812).

1321618 is an equidigital number, since it uses as much as digits as its factorization.

1321618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 660811.

The product of its digits is 288, while the sum is 22.

The square root of 1321618 is about 1149.6164577806. The cubic root of 1321618 is about 109.7409330361.

Adding to 1321618 its reverse (8161231), we get a palindrome (9482849).

The spelling of 1321618 in words is "one million, three hundred twenty-one thousand, six hundred eighteen".