21121022012220 has 72 divisors (see below), whose sum is σ = 68995338580896. Its totient is φ = 5199020802432.

The previous prime is 21121022012219. The next prime is 21121022012239. The reversal of 21121022012220 is 2221022012112.

It is a happy number.

21121022012220 is a `hidden beast` number, since 2 + 1 + 1 + 210 + 220 + 12 + 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 = 21121022012193 and 21121022012202.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4513036552 + ... + 4513041231.

Almost surely, 2^{21121022012220} is an apocalyptic number.

21121022012220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21121022012220 is an abundant number, since it is smaller than the sum of its proper divisors (47874316568676).

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

21121022012220 is a wasteful number, since it uses less digits than its factorization.

21121022012220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9026077811 (or 9026077806 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 21121022012220 its reverse (2221022012112), we get a palindrome (23342044024332).

The spelling of 21121022012220 in words is "twenty-one trillion, one hundred twenty-one billion, twenty-two million, twelve thousand, two hundred twenty".