1221302023100 has 72 divisors (see below), whose sum is σ = 2687280221808. Its totient is φ = 481694169600.

The previous prime is 1221302023099. The next prime is 1221302023159. The reversal of 1221302023100 is 13202031221.

It is a super-2 number, since 2×1221302023100² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 28499690 + ... + 28542510.

It is an arithmetic number, because the mean of its divisors is an integer number (37323336414).

Almost surely, 2^{1221302023100} is an apocalyptic number.

1221302023100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221302023100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1343640110904).

1221302023100 is an abundant number, since it is smaller than the sum of its proper divisors (1465978198708).

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

1221302023100 is a wasteful number, since it uses less digits than its factorization.

1221302023100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46815 (or 46808 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 1221302023100 its reverse (13202031221), we get a palindrome (1234504054321).

The spelling of 1221302023100 in words is "one trillion, two hundred twenty-one billion, three hundred two million, twenty-three thousand, one hundred".