20121000320 has 64 divisors (see below), whose sum is σ = 49220479440. Its totient is φ = 7861217280.

The previous prime is 20121000311. The next prime is 20121000329. The reversal of 20121000320 is 2300012102.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (20121000311) and next prime (20121000329).

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20121000329) 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, 338051 + ... + 393090.

Almost surely, 2^20121000320 is an apocalyptic number.

20121000320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20121000320 is an abundant number, since it is smaller than the sum of its proper divisors (29099479120).

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

20121000320 is an equidigital number, since it uses as much as digits as its factorization.

20121000320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 731203 (or 731191 counting only the distinct ones).

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

Adding to 20121000320 its reverse (2300012102), we get a palindrome (22421012422).

The spelling of 20121000320 in words is "twenty billion, one hundred twenty-one million, three hundred twenty", and thus it is an aban number.