1189439989 has 2 divisors, whose sum is σ = 1189439990. Its totient is φ = 1189439988.

The previous prime is 1189439929. The next prime is 1189440019. The reversal of 1189439989 is 9899349811.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1086823089 + 102616900 = 32967^2 + 10130^2 .

It is a cyclic number.

It is not a de Polignac number, because 1189439989 - 2¹¹ = 1189437941 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1189439929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 594719994 + 594719995.

It is an arithmetic number, because the mean of its divisors is an integer number (594719995).

Almost surely, 2^1189439989 is an apocalyptic number.

It is an amenable number.

1189439989 is a deficient number, since it is larger than the sum of its proper divisors (1).

1189439989 is an equidigital number, since it uses as much as digits as its factorization.

1189439989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5038848, while the sum is 61.

The square root of 1189439989 is about 34488.2587122052. The cubic root of 1189439989 is about 1059.5322455609.

The spelling of 1189439989 in words is "one billion, one hundred eighty-nine million, four hundred thirty-nine thousand, nine hundred eighty-nine".