21034121020 has 24 divisors (see below), whose sum is σ = 48187259568. Its totient is φ = 7648771200.

The previous prime is 21034120997. The next prime is 21034121033. The reversal of 21034121020 is 2012143012.

It is a junction number, because it is equal to n+sod(n) for n = 21034120985 and 21034121003.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 47804601 + ... + 47805040.

It is an arithmetic number, because the mean of its divisors is an integer number (2007802482).

Almost surely, 2^21034121020 is an apocalyptic number.

21034121020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21034121020 is an abundant number, since it is smaller than the sum of its proper divisors (27153138548).

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

21034121020 is a wasteful number, since it uses less digits than its factorization.

21034121020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95609661 (or 95609659 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 21034121020 its reverse (2012143012), we get a palindrome (23046264032).

It can be divided in two parts, 210341 and 21020, that added together give a square (231361 = 481²).

The spelling of 21034121020 in words is "twenty-one billion, thirty-four million, one hundred twenty-one thousand, twenty".