21001200320 has 28 divisors (see below), whose sum is σ = 50009109024. Its totient is φ = 8400480000.

The previous prime is 21001200307. The next prime is 21001200379. The reversal of 21001200320 is 2300210012.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32814056 + ... + 32814695.

It is an arithmetic number, because the mean of its divisors is an integer number (1786039608).

Almost surely, 2^21001200320 is an apocalyptic number.

21001200320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21001200320 is an abundant number, since it is smaller than the sum of its proper divisors (29007908704).

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

21001200320 is an equidigital number, since it uses as much as digits as its factorization.

21001200320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65628768 (or 65628758 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 11.

Adding to 21001200320 its reverse (2300210012), we get a palindrome (23301410332).

The spelling of 21001200320 in words is "twenty-one billion, one million, two hundred thousand, three hundred twenty".