1989847 has 2 divisors, whose sum is σ = 1989848. Its totient is φ = 1989846.

The previous prime is 1989811. The next prime is 1989863. The reversal of 1989847 is 7489891.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1989847 - 2¹⁵ = 1957079 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 1989797 and 1989806.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1989877) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 994923 + 994924.

It is an arithmetic number, because the mean of its divisors is an integer number (994924).

2^1989847 is an apocalyptic number.

1989847 is a deficient number, since it is larger than the sum of its proper divisors (1).

1989847 is an equidigital number, since it uses as much as digits as its factorization.

1989847 is an evil number, because the sum of its binary digits is even.

The product of its digits is 145152, while the sum is 46.

The square root of 1989847 is about 1410.6193675120. The cubic root of 1989847 is about 125.7785435589.

The spelling of 1989847 in words is "one million, nine hundred eighty-nine thousand, eight hundred forty-seven".