1221122221002 has 32 divisors (see below), whose sum is σ = 2715287463360. Its totient is φ = 406788361200.

The previous prime is 1221122220979. The next prime is 1221122221003. The reversal of 1221122221002 is 2001222211221.

It is a happy number.

It is a super-2 number, since 2×1221122221002² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (1221122221003) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6922624 + ... + 7096827.

It is an arithmetic number, because the mean of its divisors is an integer number (84852733230).

Almost surely, 2^{1221122221002} is an apocalyptic number.

1221122221002 is an abundant number, since it is smaller than the sum of its proper divisors (1494165242358).

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

1221122221002 is a wasteful number, since it uses less digits than its factorization.

1221122221002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14021075 (or 14021069 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 1221122221002 its reverse (2001222211221), we get a palindrome (3222344432223).

The spelling of 1221122221002 in words is "one trillion, two hundred twenty-one billion, one hundred twenty-two million, two hundred twenty-one thousand, two".