1200129989 has 2 divisors, whose sum is σ = 1200129990. Its totient is φ = 1200129988.

The previous prime is 1200129979. The next prime is 1200130021. The reversal of 1200129989 is 9899210021.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 881793025 + 318336964 = 29695^2 + 17842^2 .

It is an emirp because it is prime and its reverse (9899210021) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1200129989 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1200129919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 600064994 + 600064995.

It is an arithmetic number, because the mean of its divisors is an integer number (600064995).

Almost surely, 2^1200129989 is an apocalyptic number.

It is an amenable number.

1200129989 is a deficient number, since it is larger than the sum of its proper divisors (1).

1200129989 is an equidigital number, since it uses as much as digits as its factorization.

1200129989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23328, while the sum is 41.

The square root of 1200129989 is about 34642.8923301736. The cubic root of 1200129989 is about 1062.6969383319.

The spelling of 1200129989 in words is "one billion, two hundred million, one hundred twenty-nine thousand, nine hundred eighty-nine".