1989769 has 2 divisors, whose sum is σ = 1989770. Its totient is φ = 1989768.

The previous prime is 1989721. The next prime is 1989787. The reversal of 1989769 is 9679891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1471369 + 518400 = 1213^2 + 720^2 .

It is a cyclic number.

It is not a de Polignac number, because 1989769 - 2¹⁹ = 1465481 is a prime.

It is a super-2 number, since 2×1989769² = 7918361346722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1986769) by changing a digit.

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

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 994884 + 994885.

It is an arithmetic number, because the mean of its divisors is an integer number (994885).

2^1989769 is an apocalyptic number.

It is an amenable number.

1989769 is a deficient number, since it is larger than the sum of its proper divisors (1).

1989769 is an equidigital number, since it uses as much as digits as its factorization.

1989769 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 244944, while the sum is 49.

The square root of 1989769 is about 1410.5917198112. The cubic root of 1989769 is about 125.7769000733.

The spelling of 1989769 in words is "one million, nine hundred eighty-nine thousand, seven hundred sixty-nine".