1220123381 has 2 divisors, whose sum is σ = 1220123382. Its totient is φ = 1220123380.

The previous prime is 1220123357. The next prime is 1220123449. The reversal of 1220123381 is 1833210221.

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., 1190595025 + 29528356 = 34505^2 + 5434^2 .

It is an emirp because it is prime and its reverse (1833210221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1220123381 - 2²⁶ = 1153014517 is a prime.

It is a super-2 number, since 2×1220123381² = 2977402129725742322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1220123341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610061690 + 610061691.

It is an arithmetic number, because the mean of its divisors is an integer number (610061691).

Almost surely, 2^1220123381 is an apocalyptic number.

It is an amenable number.

1220123381 is a deficient number, since it is larger than the sum of its proper divisors (1).

1220123381 is an equidigital number, since it uses as much as digits as its factorization.

1220123381 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 1220123381 is about 34930.2645423707. The cubic root of 1220123381 is about 1068.5657497725.

The spelling of 1220123381 in words is "one billion, two hundred twenty million, one hundred twenty-three thousand, three hundred eighty-one".