1438206989 has 2 divisors, whose sum is σ = 1438206990. Its totient is φ = 1438206988.

The previous prime is 1438206967. The next prime is 1438207019. The reversal of 1438206989 is 9896028341.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1352032900 + 86174089 = 36770^2 + 9283^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1438206989 is a prime.

It is a super-2 number, since 2×1438206989² = 4136878686416892242, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1431206989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 719103494 + 719103495.

It is an arithmetic number, because the mean of its divisors is an integer number (719103495).

Almost surely, 2^1438206989 is an apocalyptic number.

It is an amenable number.

1438206989 is a deficient number, since it is larger than the sum of its proper divisors (1).

1438206989 is an equidigital number, since it uses as much as digits as its factorization.

1438206989 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 746496, while the sum is 50.

The square root of 1438206989 is about 37923.6995690030. The cubic root of 1438206989 is about 1128.7743488953.

The spelling of 1438206989 in words is "one billion, four hundred thirty-eight million, two hundred six thousand, nine hundred eighty-nine".