101221020020 has 12 divisors (see below), whose sum is σ = 212564142084. Its totient is φ = 40488408000.

The previous prime is 101221020011. The next prime is 101221020023. The reversal of 101221020020 is 20020122101.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 47736132196 + 53484887824 = 218486^2 + 231268^2 .

It is a junction number, because it is equal to n+sod(n) for n = 101221019983 and 101221020010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (101221020023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2530525481 + ... + 2530525520.

It is an arithmetic number, because the mean of its divisors is an integer number (17713678507).

Almost surely, 2^101221020020 is an apocalyptic number.

101221020020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

101221020020 is an abundant number, since it is smaller than the sum of its proper divisors (111343122064).

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

101221020020 is a wasteful number, since it uses less digits than its factorization.

101221020020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5061051010 (or 5061051008 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 101221020020 its reverse (20020122101), we get a palindrome (121241142121).

The spelling of 101221020020 in words is "one hundred one billion, two hundred twenty-one million, twenty thousand, twenty".