1221210112020 has 96 divisors (see below), whose sum is σ = 3438974085120. Its totient is φ = 323792394240.

The previous prime is 1221210111991. The next prime is 1221210112027. The reversal of 1221210112020 is 202110121221.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221210112027) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 24373314 + ... + 24423366.

It is an arithmetic number, because the mean of its divisors is an integer number (35822646720).

Almost surely, 2^{1221210112020} is an apocalyptic number.

1221210112020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221210112020 is an abundant number, since it is smaller than the sum of its proper divisors (2217763973100).

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

1221210112020 is a wasteful number, since it uses less digits than its factorization.

1221210112020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52385 (or 52383 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 1221210112020 its reverse (202110121221), we get a palindrome (1423320233241).

The spelling of 1221210112020 in words is "one trillion, two hundred twenty-one billion, two hundred ten million, one hundred twelve thousand, twenty".