1243432189 has 2 divisors, whose sum is σ = 1243432190. Its totient is φ = 1243432188.

The previous prime is 1243432123. The next prime is 1243432231. The reversal of 1243432189 is 9812343421.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 631265625 + 612166564 = 25125^2 + 24742^2 .

It is a cyclic number.

It is not a de Polignac number, because 1243432189 - 2⁷ = 1243432061 is a prime.

It is a super-2 number, since 2×1243432189² = 3092247217282663442, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1243402189) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 621716094 + 621716095.

It is an arithmetic number, because the mean of its divisors is an integer number (621716095).

Almost surely, 2^1243432189 is an apocalyptic number.

It is an amenable number.

1243432189 is a deficient number, since it is larger than the sum of its proper divisors (1).

1243432189 is an equidigital number, since it uses as much as digits as its factorization.

1243432189 is an evil number, because the sum of its binary digits is even.

The product of its digits is 41472, while the sum is 37.

The square root of 1243432189 is about 35262.3338563970. Note that the first 3 decimals coincide. The cubic root of 1243432189 is about 1075.3273750359.

The spelling of 1243432189 in words is "one billion, two hundred forty-three million, four hundred thirty-two thousand, one hundred eighty-nine".