1221100010988 has 216 divisors, whose sum is σ = 3396087261504. Its totient is φ = 341078474880.

The previous prime is 1221100010981. The next prime is 1221100010993. The reversal of 1221100010988 is 8890100011221.

It is a super-2 number, since 2×1221100010988² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (1221100010981) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 193117195 + ... + 193123517.

Almost surely, 2^{1221100010988} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221100010988, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1698043630752).

1221100010988 is an abundant number, since it is smaller than the sum of its proper divisors (2174987250516).

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

1221100010988 is a wasteful number, since it uses less digits than its factorization.

1221100010988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7165 (or 7139 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 33.

The spelling of 1221100010988 in words is "one trillion, two hundred twenty-one billion, one hundred million, ten thousand, nine hundred eighty-eight".