1221310012220 has 24 divisors (see below), whose sum is σ = 2599884604464. Its totient is φ = 481831894656.

The previous prime is 1221310012183. The next prime is 1221310012231. The reversal of 1221310012220 is 222100131221.

It is a congruent number.

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, 418255394 + ... + 418258313.

It is an arithmetic number, because the mean of its divisors is an integer number (108328525186).

Almost surely, 2^{1221310012220} is an apocalyptic number.

1221310012220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221310012220 is an abundant number, since it is smaller than the sum of its proper divisors (1378574592244).

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

1221310012220 is a wasteful number, since it uses less digits than its factorization.

1221310012220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 836513789 (or 836513787 counting only the distinct ones).

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

Adding to 1221310012220 its reverse (222100131221), we get a palindrome (1443410143441).

The spelling of 1221310012220 in words is "one trillion, two hundred twenty-one billion, three hundred ten million, twelve thousand, two hundred twenty".