21031033620 has 24 divisors (see below), whose sum is σ = 58886894304. Its totient is φ = 5608275616.

The previous prime is 21031033619. The next prime is 21031033627. The reversal of 21031033620 is 2633013012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21031033627) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 175258554 + ... + 175258673.

It is an arithmetic number, because the mean of its divisors is an integer number (2453620596).

Almost surely, 2^21031033620 is an apocalyptic number.

21031033620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21031033620 is an abundant number, since it is smaller than the sum of its proper divisors (37855860684).

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

21031033620 is a wasteful number, since it uses less digits than its factorization.

21031033620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 350517239 (or 350517237 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 21.

Adding to 21031033620 its reverse (2633013012), we get a palindrome (23664046632).

The spelling of 21031033620 in words is "twenty-one billion, thirty-one million, thirty-three thousand, six hundred twenty".