1221203121123 has 8 divisors (see below), whose sum is σ = 1628450446528. Its totient is φ = 814045604904.

The previous prime is 1221203121091. The next prime is 1221203121161. The reversal of 1221203121123 is 3211213021221.

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

It is not a de Polignac number, because 1221203121123 - 2⁵ = 1221203121091 is a prime.

It is a super-2 number, since 2×1221203121123² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1221203121123.

It is not an unprimeable number, because it can be changed into a prime (1221203125123) 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, 22420561 + ... + 22474962.

It is an arithmetic number, because the mean of its divisors is an integer number (203556305816).

Almost surely, 2^{1221203121123} is an apocalyptic number.

1221203121123 is a deficient number, since it is larger than the sum of its proper divisors (407247325405).

1221203121123 is an equidigital number, since it uses as much as digits as its factorization.

1221203121123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44904593.

The product of its (nonzero) digits is 288, while the sum is 21.

Adding to 1221203121123 its reverse (3211213021221), we get a palindrome (4432416142344).

The spelling of 1221203121123 in words is "one trillion, two hundred twenty-one billion, two hundred three million, one hundred twenty-one thousand, one hundred twenty-three".