21230131021020 has 144 divisors (see below), whose sum is σ = 65069092827648. Its totient is φ = 5602675455360.

The previous prime is 21230131021013. The next prime is 21230131021079. The reversal of 21230131021020 is 2012013103212.

21230131021020 is a `hidden beast` number, since 2 + 12 + 301 + 310 + 21 + 0 + 20 = 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 = 21230131020984 and 21230131021002.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5267985 + ... + 8379255.

It is an arithmetic number, because the mean of its divisors is an integer number (451868700192).

Almost surely, 2^{21230131021020} is an apocalyptic number.

21230131021020 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 21230131021020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32534546413824).

21230131021020 is an abundant number, since it is smaller than the sum of its proper divisors (43838961806628).

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

21230131021020 is a wasteful number, since it uses less digits than its factorization.

21230131021020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3111680 (or 3111675 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 21230131021020 its reverse (2012013103212), we get a palindrome (23242144124232).

The spelling of 21230131021020 in words is "twenty-one trillion, two hundred thirty billion, one hundred thirty-one million, twenty-one thousand, twenty".