1221131003100 has 36 divisors (see below), whose sum is σ = 3533139036504. Its totient is φ = 325634934080.

The previous prime is 1221131003087. The next prime is 1221131003117. The reversal of 1221131003100 is 13001311221.

It is a happy number.

It is a super-2 number, since 2×1221131003100² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 1221131003100.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2035218039 + ... + 2035218638.

It is an arithmetic number, because the mean of its divisors is an integer number (98142751014).

Almost surely, 2^{1221131003100} is an apocalyptic number.

1221131003100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221131003100 is an abundant number, since it is smaller than the sum of its proper divisors (2312008033404).

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

1221131003100 is a wasteful number, since it uses less digits than its factorization.

1221131003100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4070436694 (or 4070436687 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 15.

Adding to 1221131003100 its reverse (13001311221), we get a palindrome (1234132314321).

The spelling of 1221131003100 in words is "one trillion, two hundred twenty-one billion, one hundred thirty-one million, three thousand, one hundred".