21031003320 has 32 divisors (see below), whose sum is σ = 63093010320. Its totient is φ = 5608267520.

The previous prime is 21031003267. The next prime is 21031003321. The reversal of 21031003320 is 2330013012.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21031003320.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21031003321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 87629061 + ... + 87629300.

Almost surely, 2^21031003320 is an apocalyptic number.

21031003320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21031003320 is an abundant number, since it is smaller than the sum of its proper divisors (42062007000).

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

21031003320 is a wasteful number, since it uses less digits than its factorization.

21031003320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 175258375 (or 175258371 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 15.

Adding to 21031003320 its reverse (2330013012), we get a palindrome (23361016332).

The spelling of 21031003320 in words is "twenty-one billion, thirty-one million, three thousand, three hundred twenty".