1618646 has 4 divisors (see below), whose sum is σ = 2427972. Its totient is φ = 809322.

The previous prime is 1618637. The next prime is 1618663. The reversal of 1618646 is 6468161.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 6468161 = 7 ⋅924023.

It is a super-5 number, since 5×1618646⁵ (a number of 32 digits) contains 55555 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 404660 + ... + 404663.

It is an arithmetic number, because the mean of its divisors is an integer number (606993).

2^1618646 is an apocalyptic number.

1618646 is a deficient number, since it is larger than the sum of its proper divisors (809326).

1618646 is an equidigital number, since it uses as much as digits as its factorization.

1618646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 809325.

The product of its digits is 6912, while the sum is 32.

The square root of 1618646 is about 1272.2601935139. The cubic root of 1618646 is about 117.4132995544.

The spelling of 1618646 in words is "one million, six hundred eighteen thousand, six hundred forty-six".