210121022221020 has 192 divisors, whose sum is σ = 676274558198400. Its totient is φ = 54098285875200.

The previous prime is 210121022220983. The next prime is 210121022221043. The reversal of 210121022221020 is 20122220121012.

It is a happy number.

210121022221020 is a `hidden beast` number, since 2 + 1 + 0 + 1 + 210 + 222 + 210 + 20 = 666.

It is a super-2 number, since 2×210121022221020² (a number of 29 digits) contains 22 as substring.

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 = 210121022220984 and 210121022221002.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 494659362 + ... + 495083958.

It is an arithmetic number, because the mean of its divisors is an integer number (3522263323950).

Almost surely, 2^{210121022221020} is an apocalyptic number.

210121022221020 is a gapful number since it is divisible by the number (20) 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 210121022221020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (338137279099200).

210121022221020 is an abundant number, since it is smaller than the sum of its proper divisors (466153535977380).

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

210121022221020 is a wasteful number, since it uses less digits than its factorization.

210121022221020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 456245 (or 456237 counting only the distinct ones).

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

Adding to 210121022221020 its reverse (20122220121012), we get a palindrome (230243242342032).

The spelling of 210121022221020 in words is "two hundred ten trillion, one hundred twenty-one billion, twenty-two million, two hundred twenty-one thousand, twenty".