1220120989 has 2 divisors, whose sum is σ = 1220120990. Its totient is φ = 1220120988.

The previous prime is 1220120983. The next prime is 1220121017. The reversal of 1220120989 is 9890210221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1102572025 + 117548964 = 33205^2 + 10842^2 .

It is an emirp because it is prime and its reverse (9890210221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1220120989 - 2³ = 1220120981 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1220120981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610060494 + 610060495.

It is an arithmetic number, because the mean of its divisors is an integer number (610060495).

Almost surely, 2^1220120989 is an apocalyptic number.

It is an amenable number.

1220120989 is a deficient number, since it is larger than the sum of its proper divisors (1).

1220120989 is an equidigital number, since it uses as much as digits as its factorization.

1220120989 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 34.

The square root of 1220120989 is about 34930.2303027048. The cubic root of 1220120989 is about 1068.5650514795.

The spelling of 1220120989 in words is "one billion, two hundred twenty million, one hundred twenty thousand, nine hundred eighty-nine".