1989647 has 8 divisors (see below), whose sum is σ = 2184192. Its totient is φ = 1797400.

The previous prime is 1989643. The next prime is 1989671. The reversal of 1989647 is 7469891.

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

It is not a de Polignac number, because 1989647 - 2² = 1989643 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1989598 and 1989607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1989643) 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, 1628 + ... + 2574.

It is an arithmetic number, because the mean of its divisors is an integer number (273024).

2^1989647 is an apocalyptic number.

1989647 is a deficient number, since it is larger than the sum of its proper divisors (194545).

1989647 is a wasteful number, since it uses less digits than its factorization.

1989647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1149.

The product of its digits is 108864, while the sum is 44.

The square root of 1989647 is about 1410.5484748849. The cubic root of 1989647 is about 125.7743294072.

The spelling of 1989647 in words is "one million, nine hundred eighty-nine thousand, six hundred forty-seven".