221121001211220 has 144 divisors (see below), whose sum is σ = 734313445145280. Its totient is φ = 53414325619200.

The previous prime is 221121001211057. The next prime is 221121001211221. The reversal of 221121001211220 is 22112100121122.

221121001211220 is a `hidden beast` number, since 2 + 21 + 1 + 210 + 0 + 1 + 211 + 220 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 221121001211193 and 221121001211202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221121001211221) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 198157630 + ... + 199270389.

It is an arithmetic number, because the mean of its divisors is an integer number (5099398924620).

Almost surely, 2^{221121001211220} is an apocalyptic number.

221121001211220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221121001211220 is an abundant number, since it is smaller than the sum of its proper divisors (513192443934060).

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

221121001211220 is a wasteful number, since it uses less digits than its factorization.

221121001211220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 397428326 (or 397428321 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 221121001211220 its reverse (22112100121122), we get a palindrome (243233101332342).

The spelling of 221121001211220 in words is "two hundred twenty-one trillion, one hundred twenty-one billion, one million, two hundred eleven thousand, two hundred twenty".