1221123221000 has 32 divisors (see below), whose sum is σ = 2857428339480. Its totient is φ = 488449288000.

The previous prime is 1221123220997. The next prime is 1221123221023. The reversal of 1221123221000 is 1223211221.

It can be written as a sum of positive squares in 4 ways, for example, as 759780695716 + 461342525284 = 871654^2 + 679222^2 .

It is a super-2 number, since 2×1221123221000² (a number of 25 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1221123221000.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 610560611 + ... + 610562610.

Almost surely, 2^{1221123221000} is an apocalyptic number.

1221123221000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221123221000 is an abundant number, since it is smaller than the sum of its proper divisors (1636305118480).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1221123221000 is a wasteful number, since it uses less digits than its factorization.

1221123221000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1221123242 (or 1221123228 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 1221123221000 its reverse (1223211221), we get a palindrome (1222346432221).

The spelling of 1221123221000 in words is "one trillion, two hundred twenty-one billion, one hundred twenty-three million, two hundred twenty-one thousand".