10211221020 has 768 divisors, whose sum is σ = 41504182272. Its totient is φ = 1804861440.

The previous prime is 10211220953. The next prime is 10211221049. The reversal of 10211221020 is 2012211201.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 10211220987 and 10211221005.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 74534392 + ... + 74534528.

It is an arithmetic number, because the mean of its divisors is an integer number (54041904).

Almost surely, 2^10211221020 is an apocalyptic number.

10211221020 is a gapful number since it is divisible by the number (10) 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 10211221020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20752091136).

10211221020 is an abundant number, since it is smaller than the sum of its proper divisors (31292961252).

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

10211221020 is a wasteful number, since it uses less digits than its factorization.

10211221020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 270 (or 268 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 10211221020 its reverse (2012211201), we get a palindrome (12223432221).

The spelling of 10211221020 in words is "ten billion, two hundred eleven million, two hundred twenty-one thousand, twenty".