1986646 has 4 divisors (see below), whose sum is σ = 2979972. Its totient is φ = 993322.

The previous prime is 1986631. The next prime is 1986679. The reversal of 1986646 is 6466891.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 6466891 = 257 ⋅25163.

It is a junction number, because it is equal to n+sod(n) for n = 1986599 and 1986608.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 496660 + ... + 496663.

It is an arithmetic number, because the mean of its divisors is an integer number (744993).

2^1986646 is an apocalyptic number.

1986646 is a deficient number, since it is larger than the sum of its proper divisors (993326).

1986646 is an equidigital number, since it uses as much as digits as its factorization.

1986646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 993325.

The product of its digits is 62208, while the sum is 40.

The square root of 1986646 is about 1409.4843028569. The cubic root of 1986646 is about 125.7110621222.

The spelling of 1986646 in words is "one million, nine hundred eighty-six thousand, six hundred forty-six".