1221012123 has 8 divisors (see below), whose sum is σ = 1638798336. Its totient is φ = 808617000.

The previous prime is 1221012119. The next prime is 1221012137. The reversal of 1221012123 is 3212101221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1221012123 - 2² = 1221012119 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1221010123) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1347243 + ... + 1348148.

It is an arithmetic number, because the mean of its divisors is an integer number (204849792).

Almost surely, 2^1221012123 is an apocalyptic number.

1221012123 is a deficient number, since it is larger than the sum of its proper divisors (417786213).

1221012123 is a wasteful number, since it uses less digits than its factorization.

1221012123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2695545.

The product of its (nonzero) digits is 48, while the sum is 15.

The square root of 1221012123 is about 34942.9838880425. The cubic root of 1221012123 is about 1068.8251357730.

Adding to 1221012123 its reverse (3212101221), we get a palindrome (4433113344).

The spelling of 1221012123 in words is "one billion, two hundred twenty-one million, twelve thousand, one hundred twenty-three".