101211221020 has 192 divisors, whose sum is σ = 263770214400. Its totient is φ = 31766372352.

The previous prime is 101211221009. The next prime is 101211221021. The reversal of 101211221020 is 20122112101.

It is a super-2 number, since 2×101211221020² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (101211221021) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 168966681 + ... + 168967279.

It is an arithmetic number, because the mean of its divisors is an integer number (1373803200).

Almost surely, 2^101211221020 is an apocalyptic number.

101211221020 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 101211221020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (131885107200).

101211221020 is an abundant number, since it is smaller than the sum of its proper divisors (162558993380).

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

101211221020 is a wasteful number, since it uses less digits than its factorization.

101211221020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1244 (or 1242 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 101211221020 its reverse (20122112101), we get a palindrome (121333333121).

The spelling of 101211221020 in words is "one hundred one billion, two hundred eleven million, two hundred twenty-one thousand, twenty".