21033115420 has 12 divisors (see below), whose sum is σ = 44169542424. Its totient is φ = 8413246160.

The previous prime is 21033115409. The next prime is 21033115427. The reversal of 21033115420 is 2451133012.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21033115391 and 21033115400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21033115427) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 525827866 + ... + 525827905.

It is an arithmetic number, because the mean of its divisors is an integer number (3680795202).

Almost surely, 2^21033115420 is an apocalyptic number.

21033115420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21033115420 is an abundant number, since it is smaller than the sum of its proper divisors (23136427004).

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

21033115420 is a wasteful number, since it uses less digits than its factorization.

21033115420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1051655780 (or 1051655778 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 22.

Adding to 21033115420 its reverse (2451133012), we get a palindrome (23484248432).

The spelling of 21033115420 in words is "twenty-one billion, thirty-three million, one hundred fifteen thousand, four hundred twenty".